Gm 3973487x

x2 Summit Racing SUM-152123 - Summit Racing™ Cast Iron Cylinder Heads for Small Chevy. Cylinder Head, Cast Iron, Assembled, 72cc Chamber, 165cc Intake Runner, Chevy, 302, 327, 350, 400, Each. Part Number: SUM-152123. ( 112 ) Estimated Ship Date: 3/23/2022 (if ordered today) Free Shipping. Jan 10, 2007 · 3973487X 350 71-72 75cc, larger intake ports 3973493 400 71 76cc 3986316 350 71 Corvette, 76cc 3986336X 350 76cc 3986388 307,350 68-76 3986339 307,350 71 74.5cc 3986339X 307,350 71 74.5cc 3991492 350 70 "Camel Hump" head, LT1, 64cc, straight plug 3991492 71-up Replacement head, 64cc, straight or angle plug 82 Speedway Located at 16369 US-82, Petty, TX 75470 (14 Miles West of Paris, 25 Miles East of Bonham) www.82Speedway.com Tracy Peters 214-682-8460Chevrolet Performance’s Fast-Burn 23-degree cylinder heads deliver maximum performance for Small-Block engines. An aluminum head casting – distinguished by Chevy Bowtie logos at each end – and a valvetrain with high-rpm, LS-style beehive-type valve springs stretches the performance range of the heads to enable greater power at a higher rpm. 72 1972 350 CHEVELLE Corvette Nova SS Camaro Cylinder Heads 3973487X. $150 (fairview) pic hide this posting restore restore this posting. $100. favorite this post. Jul 5 RARE 1967 396/375 HP 4 bolt block 3902406. $5,000 (Cleveland TN) pic hide this posting restore restore this posting. $6,500. favorite this post. Jun 21Size - Maximum size of engine block: 350 General Motors (GM) .060 max. / 351 Windsor Ford .060 max./ 360 Chrysler .040 max. Ford base engines will be 289, 302, & 351(Windsor). Chrysler base engines 340 or 360. Maximum Ford engine size is 362. All engine parts must be Ford to Ford, Chrysler to Chrysler, GM to GM (no mix and match).This is what is says about your heads. "487" - 3973487, OR 3973487X. The regular casting was found on the 1971-1972 350 LT-1 engines, had 1.94/1.50" valves, 76CC combustion chambers, DO have accessory holes, intake port volume should be 161CC's, exhaust port volume should be 65CC's. The 487X had 2.02/1.60" valves.Chevelle V8 Cylinder Head Casting Numbers - 1964 through 1972. These head castings were used in various other models of the Chevrolet lineup such as the passenger car, Chevy II/Nova, Camaro and Corvette.71350SS. your 3 78487 may be the 3973487 cyl heads .The only SBC cyl heads ending in 487 are 3876487 and 3973487 (along with 3973487X) but there is no X on your cyl heads.Its pretty easy to mistake your 4th digit of "8" for the cyl heads actual number "3".It wouldn't be the first time it has happened.A number of crate motors made by GM in Mexico, may have an "M" or "ML" prefix stamped into the front pad of the block followed by a series of numbers which serialize that particular crate replacement motor. You may also see a raised casting on the block or heads of "Hecho en Mexico" which means "Made in Mexico". Many of the new GM crate motors ...OEM or OEM cast appearing replacement steel rods only - GM 5.7 inch, 6 inch or GM Vortec rod part number 10108688 allowed. Cap screw allowed. No splayed main caps. Conventional flat tappet cam and lifters only, cannot alter lifter bores. OEM firing order cannot be changed (GM: 1-8-4-3-6-5-7-2). May use oil restrictors.The LT-1 came with a 041 291, 292, 041, 186 or 187 casting number as they were 11-1 engines as well as the Z-302 engine in that era. The 10-1 engines also used the same castings. The L-82 vette used the 487 and487X heads but lower comp.8.5-9.Thatsaid they would not have been factory installed in a 67 camaro.3973487X 1972 350 165, 175 1.94/1.50 75.47 Used only in late 1972 and overlapped production with #3998993. ... Chevrolet Production GM LT1 372 Aluminum Head 170/214 . The LT-1 head was the next generation head developed for the small blocks after the L98 head. This head uses a reverse-cooling system, which means it can not be swapped onto older ...Cylinder Head Casting Number - 3973487X 1972, 350cid, LT-1 engine with 2.02" exhaust and 1.60" intake valves, and 76CC combustion chambers. The cylinder head casting number is found underneath the rocker cover, between rocker arm pedestals. Cylinder Head Date Codes - K261 and L81 K261 = November 26, 1971 3973487X 350, 75cc, larger intake port 3973493 400, 71, 76cc 3986316 350 Corvette, 71, 76cc 3986336X 350, 76cc 3986388 307, 350, 68-76 3986339 307, 350, 71, 75cc 3986339X 307, 350, 75cc 3991492 350 LT1, 70, 64cc, straight plug, camel hump 3991492 Over counter, strt or angle plug, 64cc, 157/62cc ports72 1972 350 CHEVELLE Corvette Nova SS Camaro Cylinder Heads 3973487X. $150 (fairview) pic hide this posting restore restore this posting. $100. favorite this post. Jul 5 RARE 1967 396/375 HP 4 bolt block 3902406. $5,000 (Cleveland TN) pic hide this posting restore restore this posting. $6,500. favorite this post. Jun 21cookeville > NC (wsl) + show 57 more 72 1972 350 CHEVELLE Corvette Nova SS Camaro Cylinder Heads 3973487X try the craigslist app » Android iOS CL. outer banks NC (wsl) york, PA CRV #3963512 Chevelle 454 Engine Block BBC 1970 LS6 Four Bolt Main 4 try the craigslist app » Android iOS CL.1972 S.B. Chevy Heads 3973487X - Very good condition $200 (grr > Muskegon ) pic hide this posting restore restore this posting. $10,000. favorite this post Mar 5 ... 1967 to 1972 GM Trucks $0 (mbs > OWOSSO ) pic hide this posting restore restore this posting. $0. favorite this post Feb 9This is the differences in earlier GM heads with the "SOFT" unhardened exhaust seats an the effects of not being hardned vs the later more modern Gm heads wi...Chevrolet Small Block Head Casting Numbers. Aluminum, LT5, ZR1, DOHC, 32-Valve, drivers Side. This casting # has been used in many different versions of this aluminum 18′ and 15′ Bowtie race head. Different chamber volumes, port volumes, port locations, valve sizes, etc. were used. Check this casting carefully to determine which features it ...Chevrolet Performance’s Fast-Burn 23-degree cylinder heads deliver maximum performance for Small-Block engines. An aluminum head casting – distinguished by Chevy Bowtie logos at each end – and a valvetrain with high-rpm, LS-style beehive-type valve springs stretches the performance range of the heads to enable greater power at a higher rpm. GM no bigger than a 3.1 Liter. Ford no bigger than a 3.0 Liter. Chrysler no bigger than a 3.0 Liter. Import no bigger than a 3.0 Liter. WEIGHT: 2200 MINIMUM FOR 4 CYLINDERS 2600 MINIMUM FOR 6 CYLINDER *COMPUTER MUST BE STOCK. Must use OEM crank, rod,value size, stroke, etc. No high performance or sport car engines of any kind.1972 Chevrolet Corvette LT-1 air coupes. In February 1989 we bought a 1972 Corvette LT-1 air coupe in Austin - a red car with tan leather. It had never been in an accident and the body was in great condition.The Chevy cylinder head casting codes are one of the best ways to identify a Chevy cylinder head. It is usually found on the top of the head in between two valves and the rocker arm studs. Choose Group to View Cylinder Head Codes. Select Cylinder Head Group ALL Head Codes 262, 265, 267 302, 305 or 307 302 Only 327 350 400.Chevrolet Small Block Head Casting Numbers. Aluminum, LT5, ZR1, DOHC, 32-Valve, drivers Side. This casting # has been used in many different versions of this aluminum 18′ and 15′ Bowtie race head. Different chamber volumes, port volumes, port locations, valve sizes, etc. were used. Check this casting carefully to determine which features it ...May 09, 2011 · 2,217 Posts. Discussion Starter · #1 · May 9, 2011. I'm putting my daugters 68 together and the 350 I have has the 3973487X heads. They look to be 2.02 and when I looked them up its 1971 high performance app. or truck and pass. car. I was planning on have a set of the "hump heads" gone through for $400 but these look to be in great shape. Springfield Raceway - Rules & Forms. 2022 Pure Stock Rules. 2022 Rule Changes. Cage - 70" from rear of engine block to seat belt holes in top of seat. Top halo must be minimum 40 inches across, outside to outside. Rear Hoop - May be maximum 12 inches in from bottom of opera window. Minimum one cross bar in top halo.The Complete Cylinder Head Guide for Chevy Small Block Engines. A factor more influential toward successful high-performance engine building than any other is the cylinder heads. Without adequate airflow, the engine will never make power. The areas one inch before to about a half inch after the intake valve, and similarly for the exhaust, are ...Small block chevy head castings; Casting # Combustion Chamber size CCs Intake valve Exhaust valve Production Years Misc Engine; 10033867: 62cc: 2.02: 1.60: over the counter 23 degree, angle plug, 196 cc intake runner, Aluminum3973487x heads with 175 psi compression test. Jump to Latest Follow 1 - 19 of 19 Posts ... They will save you about 30lbs on weight over stock iron heads and will give you 30-50 more horsepower then OEM GM production heads.These heads are cast in Australia and assembled by us. These heads work great on Carburetor and fuel injection engines and ...GM performance parts factory sealed CT350 engine part number 88958602 or 19258602 are allowed. Must use a gauge legal stock unaltered 500 holley 4412 2 barrel carburetor. No HP series carburetors allowed. Max of a 1 inch straight bore carburetor spacer, no tapered spacers, must be between carburetor and intake.Size - Maximum size of engine block: 350 General Motors (GM) .060 max. / 351 Windsor Ford .060 max./ 360 Chrysler .040 max. Ford base engines will be 289, 302, & 351(Windsor). Chrysler base engines 340 or 360. Maximum Ford engine size is 362. All engine parts must be Ford to Ford, Chrysler to Chrysler, GM to GM (no mix and match).72 1972 350 CHEVELLE Corvette Nova SS Camaro Cylinder Heads 3973487X 1966 CHEVELLE or NOVA BUCKET SEATS try the craigslist app » Android iOS CL. 1976 Chevy Nova Super Sport Hot Rod ,500 1965 1966 1967 Chevelle Nova II Chevy SS Spinner Wheel Cover press to search craigslist. 1966-67 Chevy Nova headliner NEW Nova SS 4 speed press to search ... 98 Head #3973487X, Year - 1972, Model - Corvette, Engine - 350, change Horsepower to 200 103 Head #3998993, Year - 1972, Model - Corvette, Engine - 350, change Horsepower to 200 265 Borg-Warmer 4-Speed Component Casting Numbers, change to "Rear Bearing Retainer Casting #" GM Cylinder Heads- 3973487X worth rebuilding? Post by PJ Wrieden » Tue Nov 24, 2009 10:07 pm Just recently got a 67 Camaro with a 350 with these heads on the motor. The heads that are on it are the 3973487X heads I believe those 487 heads are the ones that are in high demand from factory stock circle track racers. At least around these parts (Oklahoma, Texas, Louisiana) the rules are very restrictive and those are the heads everybody wants... which means they are often hard to find.The castings are 3973487. Upon some quick research these are not the original heads because they were only used in 71-72. I plan to make this engine into a race build. It's not going in the C10 but I will find a different vehicle to put it in and make a track car out of, probably an F body. I plan to use a solid cam and lifters, NA with an ...2) The center of the crankshaft must be within two and one-half (2 1/2) inches of centerline of the ball joints. 2 11) Engine: 1) All engines parts must be Ford to Ford, Chrysler to Chrysler, GM to GM (no mix or match). 2) MAXIMUM Size of engine block: 350 gm .060 max. 351 Windsor ford .060 max. 360 chry. .060 max. 3) Smaller engine allowed.Small Block Chevy V8 Casting Numbers. To learn how to locate your casting numbers, casting dates and suffix codes, see Chevy V8 Casting Number Locations Page 1 and Page 2.. SBC BlocksNearly all GM heads can be identified by a three-digit number cast into the corner. SOURCE: GM chevy small block casting heads number 041. Tj & Toms Garage 3. I bought the truck and had lots of. Locating Specifications By Casting Number - Find the casting number in the numerical list of casting numbers.May 09, 2011 · 2,217 Posts. Discussion Starter · #1 · May 9, 2011. I'm putting my daugters 68 together and the 350 I have has the 3973487X heads. They look to be 2.02 and when I looked them up its 1971 high performance app. or truck and pass. car. I was planning on have a set of the "hump heads" gone through for $400 but these look to be in great shape. The castings are 3973487. Upon some quick research these are not the original heads because they were only used in 71-72. I plan to make this engine into a race build. It's not going in the C10 but I will find a different vehicle to put it in and make a track car out of, probably an F body. I plan to use a solid cam and lifters, NA with an ...The castings are 3973487. Upon some quick research these are not the original heads because they were only used in 71-72. I plan to make this engine into a race build. It's not going in the C10 but I will find a different vehicle to put it in and make a track car out of, probably an F body. I plan to use a solid cam and lifters, NA with an ...nice set of small block 487 heads one is a 487X contrary to popular belief that the X heads were superior these heads are identical in both valve size chamber cc and port flow one head was early 71 and the X head was late 71 thats it ,these heads are popular for circle track because the flow good and are legal , calltext , nightday , leave message , 239-404-22 three fiveOem Gm. Oem Gm Chrome 1965 1966 Big Block Chevy Valve Covers Z16 Chevelle 66 L78 Impala. 20s Corbin. 20s Corbin 6k Tachometer Tach 2-1 Ratio Speedster Prewar Race Car Scta Trog Lqqk. 69 70. 69 70 1969 Chevrolet Small Block Performance Cylinder Heads W/ Springs 3973370 . 1959 1960.Original GM total of 5 hubcaps 1963, 64 65 66 1967 NOVA Impala ss hubcaps. Car has power steering, all 4 power disk brakes, air conditioning, all newer interior from carpet up to the headliner to 1966 Chevy II Nova SS Super Sport 327ci 4 Barrel 4 Speed. 73 rear end. htm True 118 coded Super Sport, 327 Chevrolet V-81966 Chevrolet Nova SS ,900.Apr 19, 2007 · sbc head casting # 3973487X Discussion in ' The Hokey Ass Message Board ' started by Fireball Mezcal , Apr 19, 2007 . Joined: Aug 18, 2006 of second or third rod throws. OEM or OEM appearing replacement steel rods only - GM 5.7-inch, 6 inch or GM Vortec rod part number 10108688 allowed. Cap screw allowed. No splayed main caps. Conventional flat tappet cam and lifters only, cannot alter lifter bores. OEM firing order cannot be changed (GM: 1-8-4-3-6-5-7-2). May use oil restrictors. GM performance parts factory sealed CT350 engine part number 88958602 or 19258602 are allowed. Must use a gauge legal stock unaltered 500 holley 4412 2 barrel carburetor. No HP series carburetors allowed. Max of a 1 inch straight bore carburetor spacer, no tapered spacers, must be between carburetor and intake.Quality WEATHERSTRIP for GM ~ Ford ~ AMC ~ Mopar $0 (mbs > Worldwide Shipping) hide this posting restore restore this posting. $200. favorite this post Mar 7 1972 S.B. Chevy Heads 3973487X - Very good condition $200 (grr > Muskegon) pic hide this posting restore restore this posting. $50. favorite this post Mar 6 Map SensorGeneral Motors .. Mopar ) pic hide this posting restore restore this posting. $200. favorite this post Mar 7 1972 S.B. Chevy Heads 3973487X - Very good condition $200 (grr > Muskegon ) pic hide this posting restore restore this posting. $100. favorite this post Feb 121972 S.B. Chevy Heads 3973487X - Very good condition $150 (Muskegon) pic hide this posting restore restore this posting. $150. favorite this post Feb 15 ... New GM 1958-1962 Corvette front turn signal (898717) $120 (cmu > Saint Louis) pic hide this posting restore restore this posting. $200.GM no bigger than a 3.1 Liter. Ford no bigger than a 3.0 Liter. Chrysler no bigger than a 3.0 Liter. Import no bigger than a 3.0 Liter. WEIGHT: 2200 MINIMUM FOR 4 CYLINDERS 2600 MINIMUM FOR 6 CYLINDER *COMPUTER MUST BE STOCK. Must use OEM crank, rod,value size, stroke, etc. No high performance or sport car engines of any kind.This site is for Corvette C3 enthusiasts and has lots of information pertaining to Corvettes built between 1968 and 1982Cylinder Head Casting Number - 3973487X 1972, 350cid, LT-1 engine with 2.02" exhaust and 1.60" intake valves, and 76CC combustion chambers. The cylinder head casting number is found underneath the rocker cover, between rocker arm pedestals. Cylinder Head Date Codes - K261 and L81 K261 = November 26, 1971GM Cylinder Heads- 3973487X worth rebuilding? Post by PJ Wrieden » Tue Nov 24, 2009 10:07 pm Just recently got a 67 Camaro with a 350 with these heads on the motor.3973487X 350, 75cc, larger intake port 3973493 400, 71, 76cc 3986316 350 Corvette, 71, 76cc 3986336X 350, 76cc 3986388 307, 350, 68-76 3986339 307, 350, 71, 75cc 3986339X 307, 350, 75cc 3991492 350 LT1, 70, 64cc, straight plug, camel hump 3991492 Over counter, strt or angle plug, 64cc, 157/62cc ports1970-75 CAMARO ENGINE CASTING IDENTIFICATION. by Alan Colvin on December 4, 2013. The 1970-75 Camaros used a variety of blocks, cylinder heads, intake manifolds, exhaust manifolds, and waterpumps. In this article we will cover the identification of all these major engine components for all Camaro engines from 1970 through 1975.When GM first introduced its small-block engine to the world, it was specifically designed to give Chevrolet an edge over Ford's flathead V-8. This was in the mid-'50s, and before that, Chevrolet relied on inline six-cylinder engines to power its passenger vehicles. ... 3973487X: 1971 and 1972 350ci, 75cc chambers, 2.02/1.60-valves. 3973493nice set of small block 487 heads one is a 487X contrary to popular belief that the X heads were superior these heads are identical in both valve size chamber cc and port flow one head was early 71 and the X head was late 71 thats it ,these heads are popular for circle track because the flow good and are legal , calltext , nightday , leave message , 239-404-22 three fiveMay 09, 2011 · 2,217 Posts. Discussion Starter · #1 · May 9, 2011. I'm putting my daugters 68 together and the 350 I have has the 3973487X heads. They look to be 2.02 and when I looked them up its 1971 high performance app. or truck and pass. car. I was planning on have a set of the "hump heads" gone through for $400 but these look to be in great shape. The Chevy cylinder head casting codes are one of the best ways to identify a Chevy cylinder head. It is usually found on the top of the head in between two valves and the rocker arm studs. Choose Group to View Cylinder Head Codes. Select Cylinder Head Group ALL Head Codes 262, 265, 267 302, 305 or 307 302 Only 327 350 400.The Chevrolet Chevelle is a mid-sized automobile that was produced by Chevrolet in three generations for the 1964 through 1978 model years.Part of the General Motors (GM) A-body platform, the Chevelle was one of Chevrolet's most successful nameplates. Body styles included coupes, sedans, convertibles, and station wagons.The Super Sport versions ...Mar 23, 2004 · 2,921 Posts. #2 · Mar 23, 2004. I would say maximum valve lift is a function of the valve clearances @ TDC and the springs. What you don't want of course is the valve coming in contact with the piston. Bone stock Chevrolet, nothing special heads, maximum lift is under .5" I can't say exactly how much I suppose some of it does depend on the ... https://www.imca.com/rules/northernsportmod/ For diagrams and examples, visit the link above.... NORTHERN SPORTMOD - 2019 Revised October 2018.Looking for Chevy casting numbers ? This is a very complete list of numbers to help identify your Chevy engine block, heads and crankshaft.Feb 11, 2018 · 1980 Corvette GM Showroom Poster $200 ... 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (grr > Muskegon) pic hide this posting restore restore this posting. GM metric frame center of fuel pump must be located a minimum of 1 ¾” in front of . ... 3973487X, 3973493, 3951598, 468642, 330862, 333882, 3998920, 3998991, 1971 Chevy SB Heads 1971-3973487X - Rebuilt- 300.00 dollars. I have a set of Chevy 1971 Heads #3973487X that have been completely gone thru for sale. Heads have the 1.94 intake valves and 1.50 exhaust valves. Cast dates L-22-1. These heads were boiled, cleaned and magged for cracks. Valve seats were ground stock.kknapp, I think they're supposed to be 3973487X. I couldn't find 3978487X. 3973487x 75cc 2.02/1.94 1.60/1.50 1968-73 Corvette LT1 350 Hope this helps!Garage Sale. Corvette and high-performance Chevrolet engine parts including correct dated engine blocks, cylinder heads, intake manifolds, carburetors and more for the years 1962 to 1972 exclusively. - www.LightningSpeedShop.com - www.FastSS.comnice set of small block 487 heads one is a 487X contrary to popular belief that the X heads were superior these heads are identical in both valve size chamber cc and port flow one head was early 71 and the X head was late 71 thats it ,these heads are popular for circle track because the flow good and are legal , calltext , nightday , leave message , 239-404-22 three five1972 S.B. Chevy Heads 3973487X - Very good condition $200 (grr > Muskegon ) ... CHEVY, FORD, GM, GMC, RAM 3500HD*9' DUALLY SERVICE BODY*NEW TAKE-OFF* $3,500 (fwa > Swartz Creek, MI ) pic hide this posting restore restore this posting. $1. favorite this post Mar 7 camper / cap $1 (kzo > kalamazoo mi ) pic hide this posting restore restore this ...3973487X 350, 75cc, larger intake port 3973493 400, 71, 76cc 3986316 350 Corvette, 71, 76cc 3986336X 350, 76cc 3986388 307, 350, 68-76 ... I note that it appears GM did not make any (or perhaps very few) 327 motors with less than 8.5:1, and in automotive form those were all listed as 250 horsepower motors.This site is for Corvette C3 enthusiasts and has lots of information pertaining to Corvettes built between 1968 and 1982Looking for Chevy casting numbers ? This is a very complete list of numbers to help identify your Chevy engine block, heads and crankshaft.Feb 11, 2018 · 1980 Corvette GM Showroom Poster $200 ... 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (grr > Muskegon) pic hide this posting restore restore this posting. "487" - 3973487, OR 3973487X. The regular casting was found on the 1971-1972 350 LT-1 engines, had 1.94/1.50" valves, 76CC combustion chambers, DO have accessory holes, intake port volume should be 161CC's, exhaust port volume should be 65CC's. The 487X had 2.02/1.60" valves. "441" - 3932441. This head was found on the 1969-1970 350 engines ...72 1972 350 CHEVELLE Corvette Nova SS Camaro Cylinder Heads 3973487X 1966 CHEVELLE or NOVA BUCKET SEATS try the craigslist app » Android iOS CL. 1976 Chevy Nova Super Sport Hot Rod ,500 1965 1966 1967 Chevelle Nova II Chevy SS Spinner Wheel Cover press to search craigslist. 1966-67 Chevy Nova headliner NEW Nova SS 4 speed press to search ... i have run many 4416 and had billions of 882s and some 624's and have also done research on GM heads castings. you should do some also. 4416 are a good carb 305 58cc head to use for a 350 to pump up CR, have 1.90's put in them and run them, they work great, maybe port them a little, gasket match the runners, polish the exhausts after removign ...Cylinder Head Casting Number - 3973487X 1972, 350cid, LT-1 engine with 2.02" exhaust and 1.60" intake valves, and 76CC combustion chambers. The cylinder head casting number is found underneath the rocker cover, between rocker arm pedestals. Cylinder Head Date Codes - K261 and L81 K261 = November 26, 1971 Thay are all different. Need the year and cylinder head casting # It could be 60cc.65cc,70cc it could be anything. Ask your question again with this info. 1989 Chevy 350 t.b.i I still need the ...2,921 Posts. #2 · Mar 23, 2004. I would say maximum valve lift is a function of the valve clearances @ TDC and the springs. What you don't want of course is the valve coming in contact with the piston. Bone stock Chevrolet, nothing special heads, maximum lift is under .5" I can't say exactly how much I suppose some of it does depend on the ... Joined Oct 17, 1999. ·. 8,405 Posts. #4 · May 6, 2012 (Edited) At best about 205cfm (with 2.02/1.6 valves). By comparison '96 Vortec truck heads are about 230 cfm. The condition of the heads is more important. Worn guides and seats could make them expensive to recondition. Cracks could make them worthless.This is the differences in earlier GM heads with the "SOFT" unhardened exhaust seats an the effects of not being hardned vs the later more modern Gm heads wi...My heads have a casting #58842, just curious about the specs on these. They came out of a 76 nova 350 - Answered by a verified Chevy Mechanic3973487X 71-72 350 75cc chamber 3973493 71-72 400 76cc chamber 3986316 71 350 76cc chamber 3986336X 350 76cc chamber 3986339 71 307/350 74cc chamber 3986339X 71 307/350 74cc chamber 3986388 68-76 307/350 3991492 70 350 LT1,Camel hump,accessory holes,64cc, straight plug ...Cylinder Head ID Hier sind die Nummer für die Identifikation der Zylinderköpfe gelistet Small Block Casting numbers Casting Number CID Years Valves Comments 10065202 350 82-86 1.94/1.50 76cc 10065203 350 82-86 1.94/1.50 76cc 10065204 350 82-86 1.94/1.50 76cc 10065205 305 82-86 1.84/1.50 58cc 10065206 350 82-86 1.94/1.50 76cc 10065207 305 […]Jun 08, 2017 · The castings are 3973487. Upon some quick research these are not the original heads because they were only used in 71-72. I plan to make this engine into a race build. It’s not going in the C10 but I will find a different vehicle to put it in and make a track car out of, probably an F body. I plan to use a solid cam and lifters, NA with an ... GM 355 crate engine. Comp cam, ceramic coated headers, Edelbrock chromed aluminum highrise intake manifold, Edelbrock 650CFM carburetor HEI electronic ignition, new wires and plugs. Muncie M20 4 sp.. Dekoartikel im Sale . Chevrolet Chevelle 1972. Montreal, Quebec. $ 64,995. 1972. Chevrolet chevelle SS à vendre - Chevrolet chevelle SS usagé ...Jan 10, 2007 · 3973487X 350 71-72 75cc, larger intake ports 3973493 400 71 76cc 3986316 350 71 Corvette, 76cc 3986336X 350 76cc 3986388 307,350 68-76 3986339 307,350 71 74.5cc 3986339X 307,350 71 74.5cc 3991492 350 70 "Camel Hump" head, LT1, 64cc, straight plug 3991492 71-up Replacement head, 64cc, straight or angle plug 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (Muskegon) pic hide this posting restore restore this posting. $150. favorite this post Feb 15 ... New GM 1958-1962 Corvette front turn signal (898717) $120 (cmu > Saint Louis) pic hide this posting restore restore this posting. $200.Find many great new & used options and get the best deals for 3973487X Cylinder Heads 350 SBC SB Chevy 71 Z28 Camaro 487x Corvette Chevelle at the best online prices at eBay! Free shipping for many products! A BARE set of Chevy Open Chamber heads - 441, 487 or 993 - with "CNC-UnderCover Porting" which includes our CNC-UnderCover Machining, modifications to the intake ports, exhaust ports, chamber modifications, all the cover-up work, installing and sizing new bronze valve guide liners, machining the valve seats for your size valves and providing air flow numbers for your camshaft selection.High Nickel 350 Block w/ Master Rebuild Kit installed Heads shaved, bearing & cam surfaces machined Heads rebuilt, casting #3973487X, 76 GM heads, resurfaced .005 removed 16 new Brass valve guides, valve size 2.02 x 1.60 New SI Industries SS swirl polished valves, PC Teflon valve stem seals, & Elgin Industries 1,250 valve springs.Chevrolet Small Block Head Casting Numbers; Casting # Combustion Chamber Size (CCs) Intake Valve Exhaust Valve Production Years Misc. Engine Size (ci)Chevrolet Small Block Head Casting Numbers; Casting # Combustion Chamber Size (CCs) Intake Valve Exhaust Valve Production Years Misc. Engine Size (ci)"487" - 3973487, OR 3973487X. I write you all the numbers i found: Numbers in head casting: D 144 473 3824437 GM 7 Numbers on block D 114 3850817 C GM 22 F. A Fiero SP ported head build:. 5-to-1 compression ratio and its direct-injection system is neatly buried in the engine, leaving plenty of room under the hood for other goodies.GM Saginaw 4 speed transmission $400 (jxn > Hanover) pic hide this posting restore restore this posting. favorite this post Mar 20 ... 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (grr > Muskegon) pic hide this posting restore restore this posting. $300. favorite this post Mar 6Jun 08, 2017 · The castings are 3973487. Upon some quick research these are not the original heads because they were only used in 71-72. I plan to make this engine into a race build. It’s not going in the C10 but I will find a different vehicle to put it in and make a track car out of, probably an F body. I plan to use a solid cam and lifters, NA with an ... Discussion Starter · #1 · Dec 23, 2008. Hey Guys i've got a set of heads casting 3873487,I know for sure this is the number because i blasted them.It seems like i read a long time ago that they were Lt1 heads from the early 70's but i don't know.Does anyone out there have any info. It would be appreciated ain:Nearly all GM heads can be identified by a three-digit number cast into the corner. SOURCE: GM chevy small block casting heads number 041. Tj & Toms Garage 3. I bought the truck and had lots of. Locating Specifications By Casting Number - Find the casting number in the numerical list of casting numbers.Sep 09, 2009 · 3973487X 1972 350 165, 175 1.94/1.50 75.47 Used only in late 1972 and overlapped production with #3998993. ... Chevrolet Production GM LT1 372 Aluminum Head 170/214 . Track Promoter, Tony Dycus: email - [email protected] phone - 214-502-7406 Track Phone: (817) 478-RACE (7223) Physical Address: 6737 Hudson Village Creek Rd. Kennedale, Texas 76060 Mailing Address: 3332 CR 530B Burleson, Texas 76028 2017 FACTORY STOCK RULES- as of 5/24/17New GM 1958-1962 Corvette front turn signal (898717) $120 (Saint Louis) pic. hide this posting restore restore this posting. $20. favorite this post. Feb 10.Chevrolet Performance’s Fast-Burn 23-degree cylinder heads deliver maximum performance for Small-Block engines. An aluminum head casting – distinguished by Chevy Bowtie logos at each end – and a valvetrain with high-rpm, LS-style beehive-type valve springs stretches the performance range of the heads to enable greater power at a higher rpm. 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (grr > Muskegon) pic hide this posting restore restore this posting. favorite this post Mar 6 ... 1996 GM B Platform Chevy Impala SS Caprice Factory Service Manual $100 (fnt > Grand Blanc) pic hide this posting restore restore this posting. $100.Only GM OEM heads. numbers are: 14079267, 3986336, 3986339, 3986339X, 3986388, 3932441, 376445, 3928454, 3932454, 3876487, 3973487, 3973487X, 3973493, 3951598, 468642, 330862, 333882, 3998920, 3998991, 3998993, 3998997, 3970126 or may use Engine Quest (EQ) Stock Replacement (SR) cylinder head, part number CH350I, head must remain as produced ...Maximum 361 cubic inches (GM); 363 (Ford); 370 (Chrysler). Violation of cubic inch limit must be verified by removal of head and will result in disqualification, loss of all IMCA points for the season, $1,000 fine and a 30-day suspension. Maximum compression ratio is 9.0 to 1, no tolerance.10. C.N.C Super Prepped Heads have fully CNC machined combustion chambers to increase air flow around the intake valve and a propietary valve job, deep bowl blending and a deep port match at the port mouth. These modifications will increase airflow up to .500"-.550" lift. To gain flow above that point, the entire port will need to be reworked (which will in turn help the low and mid-lift flow ...LARGE CHAMBER PRODUCTION "ON CAR" HEADS. "487" - 3973487, OR 3973487X. The regular casting was found on the 1971-1972 350 LT-1 engines, had 1.94/1.50" valves, 76CC combustion chambers, DO have accessory holes, intake port volume should be 161CC's, exhaust port volume should be 65CC's. The 487X had 2.02/1.60" valves.8) GM approved castings: 14079267, 3986336, 3986339, 3986339x, 3986388, 3932441, 376445, 3928454, 3932454, 393493, 3876487, 3973487, 3973487x, 3973493, 3951598 ...GM 355 crate engine. Comp cam, ceramic coated headers, Edelbrock chromed aluminum highrise intake manifold, Edelbrock 650CFM carburetor HEI electronic ignition, new wires and plugs. Muncie M20 4 sp.. Dekoartikel im Sale . Chevrolet Chevelle 1972. Montreal, Quebec. $ 64,995. 1972. Chevrolet chevelle SS à vendre - Chevrolet chevelle SS usagé ...The Complete Cylinder Head Guide for Chevy Small Block Engines. A factor more influential toward successful high-performance engine building than any other is the cylinder heads. Without adequate airflow, the engine will never make power. The areas one inch before to about a half inch after the intake valve, and similarly for the exhaust, are ...GM Cylinder Heads- 3973487X worth rebuilding? Post by PJ Wrieden » Tue Nov 24, 2009 10:07 pm Just recently got a 67 Camaro with a 350 with these heads on the motor.In 1969 GM was in the middle of a parts strike, which forced them to run the 1969 Corvette production late. This, in turn, meant the 1970 production run would be shortened up with the Corvettes hitting dealer showrooms February of 1970.The 1970 Corvette featured a lot of changes including fender flares to keep stones.When GM first introduced its small-block engine to the world, it was specifically designed to give Chevrolet an edge over Ford's flathead V-8. This was in the mid-'50s, and before that, Chevrolet relied on inline six-cylinder engines to power its passenger vehicles. ... 3973487X: 1971 and 1972 350ci, 75cc chambers, 2.02/1.60-valves. 3973493Nov 25, 2009 · The LT-1 came with a 041 291, 292, 041, 186 or 187 casting number as they were 11-1 engines as well as the Z-302 engine in that era. The 10-1 engines also used the same castings. The L-82 vette used the 487 and487X heads but lower comp.8.5-9.Thatsaid they would not have been factory installed in a 67 camaro. Cylinder Head ID Hier sind die Nummer für die Identifikation der Zylinderköpfe gelistet Small Block Casting numbers Casting Number CID Years Valves Comments 10065202 350 82-86 1.94/1.50 76cc 10065203 350 82-86 1.94/1.50 76cc 10065204 350 82-86 1.94/1.50 76cc 10065205 305 82-86 1.84/1.50 58cc 10065206 350 82-86 1.94/1.50 76cc 10065207 305 […]1978 Corvette GM Showroom Poster $200 (sbn > Mentone) pic hide this posting restore restore this posting. $1. favorite this post Mar 25 ... 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (grr > Muskegon) pic hide this posting restore restore this posting. $16,500. favorite this post Mar 71972 S.B. Chevy Heads 3973487X - Very good condition $150 (grr > Muskegon) pic hide this posting restore restore this posting. favorite this post Mar 6 ... 1996 GM B Platform Chevy Impala SS Caprice Factory Service Manual $100 (fnt > Grand Blanc) pic hide this posting restore restore this posting. $100.3973487X 350, 75cc, larger intake port 3973493 400, 71, 76cc 3986316 350 Corvette, 71, 76cc 3986336X 350, 76cc 3986388 307, 350, 68-76 ... I note that it appears GM did not make any (or perhaps very few) 327 motors with less than 8.5:1, and in automotive form those were all listed as 250 horsepower motors.A number of crate motors made by GM in Mexico, may have an "M" or "ML" prefix stamped into the front pad of the block followed by a series of numbers which serialize that particular crate replacement motor. You may also see a raised casting on the block or heads of "Hecho en Mexico" which means "Made in Mexico". Many of the new GM crate motors ...8) GM approved castings: 14079267, 3986336, 3986339, 3986339x, 3986388, 3932441, 376445, 3928454, 3932454, 393493, 3876487, 3973487, 3973487x, 3973493, 3951598 ...3973487X, 3973493, 3951598, 468642, 330862, 333882, 3998920, 3998991, 3998993, 3998997, 3970126. Screw in studs and guide plates ok. 305 engines may use 305 heads (no vortec). ... #8022; Edelbrock GM#2701; Ford#7121,# 7181, #7183; Chrysler #2915. No marine type intakes allowed. No aluminum high rise or vortex intakes. Not porting, polishing or ...3973487X 71-72 350 75cc chamber 3973493 71-72 400 76cc chamber 3986316 71 350 76cc chamber 3986336X 350 76cc chamber 3986339 71 307/350 74cc chamber 3986339X 71 307/350 74cc chamber 3986388 68-76 307/350 3991492 70 350 LT1,Camel hump,accessory holes,64cc, straight plug ...A special thanks to Paul Shufelt for helping me with some of the numbers below. Finally I need help filling in some of the blank spaces in the charts. If you have any of this missing info or some of this is wrong please e-mail me. Thanks, Sum. AFR 180cc -- AFR 190cc -- AFR Race 210cc -- AFR 205cc LS1 Mongoose Street Head -- AFR 205cc LS1 ...7 GM heads that bolt on with a 12-bolt pattern. Gen I small block chevys have water jackets in the heads as welljust pointing that out so others don't think there is no cooling in a standard. 100% CNC'd 200cc Competition LT1 Cylinder Head Package. The 487X had 2. 2001-2018 Chevy/GM 4.8, 5.3, 6.0, and 6.2 Remanufactured Engine $2,600 (Allendale) hide this posting restore restore this posting. $50. favorite this post Mar 14 ... 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (Muskegon) pic hide this posting restore restore this posting. $200. favorite this post Mar 6New GM 1958-1962 Corvette front turn signal (898717) $120 (Saint Louis) pic. hide this posting restore restore this posting. $20. favorite this post. Feb 10.2,921 Posts. #2 · Mar 23, 2004. I would say maximum valve lift is a function of the valve clearances @ TDC and the springs. What you don't want of course is the valve coming in contact with the piston. Bone stock Chevrolet, nothing special heads, maximum lift is under .5" I can't say exactly how much I suppose some of it does depend on the ...Cylinder Head Casting Number - 3973487X 1972, 350cid, LT-1 engine with 2.02" exhaust and 1.60" intake valves, and 76CC combustion chambers. The cylinder head casting number is found underneath the rocker cover, between rocker arm pedestals. Cylinder Head Date Codes - K261 and L81 K261 = November 26, 1971Feb 11, 2018 · 1980 Corvette GM Showroom Poster $200 ... 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (grr > Muskegon) pic hide this posting restore restore this posting. Tracy Performance , Special Parts for Special Cars: Hot Rods, Classics, Racing and Sports Cars, Since 1970. 586-772-8901 , Fax: 855-FX-TRACY The Detroit Source for Auto Parts, Accessories, and Racing Equipment1978 Corvette GM Showroom Poster $200 (sbn > Mentone) pic hide this posting restore restore this posting. $1. favorite this post Mar 25 ... 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (grr > Muskegon) pic hide this posting restore restore this posting. $16,500. favorite this post Mar 7Cylinder Head Casting Number - 3973487X 1972, 350cid, LT-1 engine with 2.02" exhaust and 1.60" intake valves, and 76CC combustion chambers. The cylinder head casting number is found underneath the rocker cover, between rocker arm pedestals. Cylinder Head Date Codes - K261 and L81 K261 = November 26, 1971 Chevrolet Small Block Head Casting Numbers; Casting # Combustion Chamber Size (CCs) Intake Valve Exhaust Valve Production Years Misc. Engine Size (ci)The heads that are on it are the 3973487X heads I believe those 487 heads are the ones that are in high demand from factory stock circle track racers. At least around these parts (Oklahoma, Texas, Louisiana) the rules are very restrictive and those are the heads everybody wants... which means they are often hard to find. Cylinder Head Casting Number - 3973487X 1972, 350cid, LT-1 engine with 2.02" exhaust and 1.60" intake valves, and 76CC combustion chambers. The cylinder head casting number is found underneath the rocker cover, between rocker arm pedestals. Cylinder Head Date Codes - K261 and L81 K261 = November 26, 1971 Block Casting Number. CASTING#.....SIZE...YEAR...MAIN CAP BOLTS....NOTES. 140029.....350...80-84...2 330817.....400...72-80...2 355909.....262.....75....2CRATE ENGINE OPTION:Must use unaltered sealed GM 602 crate engine. All GM 602 Crate engines with Chevy logo cap seals must have IMCA Cable-Lok seals. Upon inspection, any different, altered or missing GM seal bolts will result in automatic disqualification. GM seal bolt exception is IMCA approved and issued Cable-Lok repair system, and oil pan ... Chevy Casting Number identification including Block casting numbers, cylinder head casting numbers, Crankshaft and intake casting numbers.1972 Chevrolet Corvette LT-1 air coupes. In February 1989 we bought a 1972 Corvette LT-1 air coupe in Austin - a red car with tan leather. It had never been in an accident and the body was in great condition.3973487X 1972 350 165, 175 1.94/1.50 75.47 Used only in late 1972 and overlapped production with #3998993. ... Chevrolet Production GM LT1 372 Aluminum Head 170/214 . The LT-1 head was the next generation head developed for the small blocks after the L98 head. This head uses a reverse-cooling system, which means it can not be swapped onto older ...Nov 25, 2009 · The LT-1 came with a 041 291, 292, 041, 186 or 187 casting number as they were 11-1 engines as well as the Z-302 engine in that era. The 10-1 engines also used the same castings. The L-82 vette used the 487 and487X heads but lower comp.8.5-9.Thatsaid they would not have been factory installed in a 67 camaro. Nov 24, 2009 · GM Cylinder Heads- 3973487X worth rebuilding? Post by PJ Wrieden » Tue Nov 24, 2009 10:07 pm Just recently got a 67 Camaro with a 350 with these heads on the motor. Dec 09, 2020 · The heads that are on it are the 3973487X heads I believe those 487 heads are the ones that are in high demand from factory stock circle track racers. At least around these parts (Oklahoma, Texas, Louisiana) the rules are very restrictive and those are the heads everybody wants... which means they are often hard to find. Chevrolet 3973487x Cylinder Heads. Dated C 18 2 (March 18, 1972). Used on various Chevrolet vehicles including Corvettes an Camaros. Perfect for use in a late 1972 or early 1973 vehicle or use in your own project. Appears that one head is already cut for 2.02/1.60 valves, the other is cut for small valves (obviously, it will have to be cut for the larger valves).3973487x heads. Thread starter 83gbody; Start date Aug 4, 2012; Forums. G-Body Tech Forums. Engine / Swaps / Driveability . Status Not open for further replies. 83gbody Greasemonkey. Apr 17, 2012 156 0 Oxford, Ms. Aug 4, 2012 #1 Can anybody tell me bout these heads or are they worth redoing. ... 82 Speedway Located at 16369 US-82, Petty, TX 75470 (14 Miles West of Paris, 25 Miles East of Bonham) www.82Speedway.com Tracy Peters 214-682-8460"487" - 3973487, OR 3973487X. I write you all the numbers i found: Numbers in head casting: D 144 473 3824437 GM 7 Numbers on block D 114 3850817 C GM 22 F. A Fiero SP ported head build:. 5-to-1 compression ratio and its direct-injection system is neatly buried in the engine, leaving plenty of room under the hood for other goodies.A new spark plug has been released for use in the above vehicles. The new spark plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed. The new spark plug, ACDelco Part Number 41-110, is gapped to 1.01mm (0.040 inches) when the spark plug is made.The Chevy cylinder head casting codes are one of the best ways to identify a Chevy cylinder head. It is usually found on the top of the head in between two valves and the rocker arm studs. Choose Group to View Cylinder Head Codes. Select Cylinder Head Group ALL Head Codes 262, 265, 267 302, 305 or 307 302 Only 327 350 400.The LT-1 came with a 041 291, 292, 041, 186 or 187 casting number as they were 11-1 engines as well as the Z-302 engine in that era. The 10-1 engines also used the same castings. The L-82 vette used the 487 and487X heads but lower comp.8.5-9.Thatsaid they would not have been factory installed in a 67 camaro.GM metric frame center of fuel pump must be located a minimum of 1 ¾” in front of . ... 3973487X, 3973493, 3951598, 468642, 330862, 333882, 3998920, 3998991, Dec 09, 2020 · The heads that are on it are the 3973487X heads I believe those 487 heads are the ones that are in high demand from factory stock circle track racers. At least around these parts (Oklahoma, Texas, Louisiana) the rules are very restrictive and those are the heads everybody wants... which means they are often hard to find. HerdezMemberfrom Mostly The Shop. Good Heads (thick castings) revision to a camel hump but with open chamber to lower the compression a bit. I ported a set to the size of cnc ported Brodix track 1's for a small block 408 I had. They were also angle milled to 64 cc and 2.05/ 1.60 valves used. Herdez, Jun 10, 2009. SHARE POST #3.Chevrolet Small Block Head Casting Numbers; Casting # Combustion Chamber Size (CCs) Intake Valve Exhaust Valve Production Years Misc. Engine Size (ci)Yes it will. GM. put alot of V8 engines in that year camaro. Where is the oil pressure sensor located on BMW 730 year 1989 e32? On the drivers side corner of the cylinder head.Feb 02, 2022 · Garage Sale. Corvette and high-performance Chevrolet engine parts including correct dated engine blocks, cylinder heads, intake manifolds, carburetors and more for the years 1962 to 1972 exclusively. - www.LightningSpeedShop.com - www.FastSS.com Cylinder Head Casting Number - 3973487X 1972, 350cid, LT-1 engine with 2.02" exhaust and 1.60" intake valves, and 76CC combustion chambers. The cylinder head casting number is found underneath the rocker cover, between rocker arm pedestals. Cylinder Head Date Codes - K261 and L81 K261 = November 26, 1971 2001-2018 Chevy/GM 4.8, 5.3, 6.0, and 6.2 Remanufactured Engine $2,600 (Allendale) hide this posting restore restore this posting. $50. favorite this post Mar 14 ... 1972 S.B. Chevy Heads 3973487X - Very good condition $150 (Muskegon) pic hide this posting restore restore this posting. $200. favorite this post Mar 6Chevrolet Small Block Head Casting Numbers. Aluminum, LT5, ZR1, DOHC, 32-Valve, drivers Side. This casting # has been used in many different versions of this aluminum 18′ and 15′ Bowtie race head. Different chamber volumes, port volumes, port locations, valve sizes, etc. were used. Check this casting carefully to determine which features it ..."487" - 3973487, OR 3973487X. I write you all the numbers i found: Numbers in head casting: D 144 473 3824437 GM 7 Numbers on block D 114 3850817 C GM 22 F. A Fiero SP ported head build:. 5-to-1 compression ratio and its direct-injection system is neatly buried in the engine, leaving plenty of room under the hood for other goodies.I have a good set of 1972 Small Block Chevy 3973487X heads for sale. Cast dates A-20-2, A-24-2. Translates to January 20th-24th 1972 heads. Heads have 1.94 Intake and 1.50 Exhaust valves. Heads are disassembled and were hot tanked to clean, magged for cracks, oiled and bagged for storage.Thay are all different. Need the year and cylinder head casting # It could be 60cc.65cc,70cc it could be anything. Ask your question again with this info. 1989 Chevy 350 t.b.i I still need the ...Sep 09, 2009 · 3973487X 1972 350 165, 175 1.94/1.50 75.47 Used only in late 1972 and overlapped production with #3998993. ... Chevrolet Production GM LT1 372 Aluminum Head 170/214 . GM no bigger than a 3.1 Liter. Ford no bigger than a 3.0 Liter. Chrysler no bigger than a 3.0 Liter. Import no bigger than a 3.0 Liter. WEIGHT: 2200 MINIMUM FOR 4 CYLINDERS 2600 MINIMUM FOR 6 CYLINDER *COMPUTER MUST BE STOCK. Must use OEM crank, rod,value size, stroke, etc. No high performance or sport car engines of any kind.3973487X 71-72 350 75cc chamber 3973493 71-72 400 76cc chamber 3986316 71 350 76cc chamber 3986336X 350 76cc chamber 3986339 71 307/350 74cc chamber 3986339X 71 307/350 74cc chamber 3986388 68-76 307/350 3991492 70 350 LT1,Camel hump,accessory holes,64cc, straight plug ...This site is for Corvette C3 enthusiasts and has lots of information pertaining to Corvettes built between 1968 and 1982sbc head casting # 3973487X Discussion in ' The Hokey Ass Message Board ' started by Fireball Mezcal , Apr 19, 2007 . Joined: Aug 18, 200671350SS. your 3 78487 may be the 3973487 cyl heads .The only SBC cyl heads ending in 487 are 3876487 and 3973487 (along with 3973487X) but there is no X on your cyl heads.Its pretty easy to mistake your 4th digit of "8" for the cyl heads actual number "3".It wouldn't be the first time it has happened.i have run many 4416 and had billions of 882s and some 624's and have also done research on GM heads castings. you should do some also. 4416 are a good carb 305 58cc head to use for a 350 to pump up CR, have 1.90's put in them and run them, they work great, maybe port them a little, gasket match the runners, polish the exhausts after removign ...Sep 09, 2009 · 3973487X 1972 350 165, 175 1.94/1.50 75.47 Used only in late 1972 and overlapped production with #3998993. ... Chevrolet Production GM LT1 372 Aluminum Head 170/214 . Search: Craigslist nc chevelle. About chevelle nc Craigslist 3.15. GM ‘G’ body cars may utilize a fiberglass OEM replacement roof 3.16. Hood and trunk must be able to be removed without tools ... 3973487X, 3973493, 3951598 ... Pure Stock RulesUpdated 02/13/2022. RULE BOOK DISCLAIMER: The race director shall be empowered to permit reasonable and appropriate deviations from any of the specifications herein or impose any further restrictions that in his opinion do not alter the minimum acceptable requirements. NO EXPRESSED OR IMPLIED WARRANTY OF SAFETY SHALL RESULT FROM ...High Nickel 350 Block w/ Master Rebuild Kit installed Heads shaved, bearing & cam surfaces machined Heads rebuilt, casting #3973487X, 76 GM heads, resurfaced .005 removed 16 new Brass valve guides, valve size 2.02 x 1.60 New SI Industries SS swirl polished valves, PC Teflon valve stem seals, & Elgin Industries 1,250 valve springs.3973487X sbc head question.....again The 1967 - 1972 Chevrolet & GMC Pickups Message BoardTracy Performance , Special Parts for Special Cars: Hot Rods, Classics, Racing and Sports Cars, Since 1970. 586-772-8901 , Fax: 855-FX-TRACY The Detroit Source for Auto Parts, Accessories, and Racing EquipmentSize - Maximum size of engine block: 350 General Motors (GM) .060 max. / 351 Windsor Ford .060 max./ 360 Chrysler .040 max. Ford base engines will be 289, 302, & 351(Windsor). Chrysler base engines 340 or 360. Maximum Ford engine size is 362. All engine parts must be Ford to Ford, Chrysler to Chrysler, GM to GM (no mix and match).Chevrolet Performance’s Fast-Burn 23-degree cylinder heads deliver maximum performance for Small-Block engines. An aluminum head casting – distinguished by Chevy Bowtie logos at each end – and a valvetrain with high-rpm, LS-style beehive-type valve springs stretches the performance range of the heads to enable greater power at a higher rpm. The Chevy cylinder head casting codes are one of the best ways to identify a Chevy cylinder head. It is usually found on the top of the head in between two valves and the rocker arm studs. Choose Group to View Cylinder Head Codes. Select Cylinder Head Group ALL Head Codes 262, 265, 267 302, 305 or 307 302 Only 327 350 400.Cylinder Head Casting Number - 3973487X 1972, 350cid, LT-1 engine with 2.02" exhaust and 1.60" intake valves, and 76CC combustion chambers. The cylinder head casting number is found underneath the rocker cover, between rocker arm pedestals. Cylinder Head Date Codes - K261 and L81 K261 = November 26, 1971 The castings are 3973487. Upon some quick research these are not the original heads because they were only used in 71-72. I plan to make this engine into a race build. It's not going in the C10 but I will find a different vehicle to put it in and make a track car out of, probably an F body. I plan to use a solid cam and lifters, NA with an ...Quality WEATHERSTRIP for GM ~ Ford ~ AMC ~ Mopar $0 (mbs > Worldwide Shipping) hide this posting restore restore this posting. $200. favorite this post Mar 7 1972 S.B. Chevy Heads 3973487X - Very good condition $200 (grr > Muskegon) pic hide this posting restore restore this posting. $50. favorite this post Mar 6 Map Sensor"487" - 3973487, OR 3973487X. I write you all the numbers i found: Numbers in head casting: D 144 473 3824437 GM 7 Numbers on block D 114 3850817 C GM 22 F. A Fiero SP ported head build:. 5-to-1 compression ratio and its direct-injection system is neatly buried in the engine, leaving plenty of room under the hood for other goodies.A special thanks to Paul Shufelt for helping me with some of the numbers below. Finally I need help filling in some of the blank spaces in the charts. If you have any of this missing info or some of this is wrong please e-mail me. Thanks, Sum. AFR 180cc -- AFR 190cc -- AFR Race 210cc -- AFR 205cc LS1 Mongoose Street Head -- AFR 205cc LS1 ...8) GM approved castings: 14079267, 3986336, 3986339, 3986339x, 3986388, 3932441, 376445, 3928454, 3932454, 393493, 3876487, 3973487, 3973487x, 3973493, 3951598 ...350. NO stroking or de-stroking. Engine height and setback must be in stock location +/- 1". GM metric frame center of fuel pump must be located a minimum of 1 ¾" in front of unaltered cross member. Solid motor and transmission mounts okay. No full mid plates. Maximum cranking compression 175lbs. (ignition off, engine turned over 5 times).Find many great new & used options and get the best deals for 3973487X Cylinder Heads 350 SBC SB Chevy 71 Z28 Camaro 487x Corvette Chevelle at the best online prices at eBay! Free shipping for many products!Nov 25, 2009 · The LT-1 came with a 041 291, 292, 041, 186 or 187 casting number as they were 11-1 engines as well as the Z-302 engine in that era. The 10-1 engines also used the same castings. The L-82 vette used the 487 and487X heads but lower comp.8.5-9.Thatsaid they would not have been factory installed in a 67 camaro. 3973487X 350, 75cc, larger intake port 3973493 400, 71, 76cc 3986316 350 Corvette, 71, 76cc 3986336X 350, 76cc 3986388 307, 350, 68-76 3986339 307, 350, 71, 75cc 3986339X 307, 350, 75cc 3991492 350 LT1, 70, 64cc, straight plug, camel hump 3991492 Over counter, strt or angle plug, 64cc, 157/62cc portsThe LT-1 came with a 041 291, 292, 041, 186 or 187 casting number as they were 11-1 engines as well as the Z-302 engine in that era. The 10-1 engines also used the same castings. The L-82 vette used the 487 and487X heads but lower comp.8.5-9.Thatsaid they would not have been factory installed in a 67 camaro.GM Cylinder Heads- 3973487X worth rebuilding? Post by PJ Wrieden » Tue Nov 24, 2009 10:07 pm Just recently got a 67 Camaro with a 350 with these heads on the motor.High Nickel 350 Block w/ Master Rebuild Kit installed Heads shaved, bearing & cam surfaces machined Heads rebuilt, casting #3973487X, 76 GM heads, resurfaced .005 removed 16 new Brass valve guides, valve size 2.02 x 1.60 New SI Industries SS swirl polished valves, PC Teflon valve stem seals, & Elgin Industries 1,250 valve springs.Chevy / GM SB2.2 011 275 Ported Neal Alum: 275/-2.15/1.60: 54-148/109: 235/148: 292/200: 335/221: 351/238: 356/253----Chevy / GM SB2.2 011 282 Ported Neal Alum: 282/-2.15/1.625: 54-136/104: 217/139: 288/180: 335/219: 352/237: 352/246----Chevy / GM SB2.2 011 287 Ported Neal Alum: 287/-2.17/1.60: 56-143/95: 222/137: 293/180: 340/213: 374/230: 388 ...Cylinder Head ID Hier sind die Nummer für die Identifikation der Zylinderköpfe gelistet Small Block Casting numbers Casting Number CID Years Valves Comments 10065202 350 82-86 1.94/1.50 76cc 10065203 350 82-86 1.94/1.50 76cc 10065204 350 82-86 1.94/1.50 76cc 10065205 305 82-86 1.84/1.50 58cc 10065206 350 82-86 1.94/1.50 76cc 10065207 305 […]Find many great new & used options and get the best deals for 3973487X Cylinder Heads 350 SBC SB Chevy 71 Z28 Camaro 487x Corvette Chevelle at the best online prices at eBay! Free shipping for many products!In response to budlight. "487" & 3973487, OR 3973487X. The regular casting was found on the 1971-1972 350 LT-1 engines, had 1.94/1.50" valves, 76CC combustion chambers, DO have accessory holes, intake port volume should be 161CC's, exhaust port volume should be 65CC's. The 487X had 2.02/1.60" valves. Email.A special thanks to Paul Shufelt for helping me with some of the numbers below. Finally I need help filling in some of the blank spaces in the charts. If you have any of this missing info or some of this is wrong please e-mail me. Thanks, Sum. AFR 180cc -- AFR 190cc -- AFR Race 210cc -- AFR 205cc LS1 Mongoose Street Head -- AFR 205cc LS1 ...HerdezMemberfrom Mostly The Shop. Good Heads (thick castings) revision to a camel hump but with open chamber to lower the compression a bit. I ported a set to the size of cnc ported Brodix track 1's for a small block 408 I had. They were also angle milled to 64 cc and 2.05/ 1.60 valves used. Herdez, Jun 10, 2009. SHARE POST #3.Yes it will. GM. put alot of V8 engines in that year camaro. Where is the oil pressure sensor located on BMW 730 year 1989 e32? On the drivers side corner of the cylinder head.Hier vind je allerlei Technische Informatie welke betrekking heeft op diverse Amerikaanse auto's. Alleen geregistreerde Members kunnen de topics bekijken.Chevrolet 3973487x Cylinder Heads. Dated C 18 2 (March 18, 1972). Used on various Chevrolet vehicles including Corvettes an Camaros. Perfect for use in a late 1972 or early 1973 vehicle or use in your own project. Appears that one head is already cut for 2.02/1.60 valves, the other is cut for small valves (obviously, it will have to be cut for the larger valves).Cylinder Head ID Hier sind die Nummer für die Identifikation der Zylinderköpfe gelistet Small Block Casting numbers Casting Number CID Years Valves Comments 10065202 350 82-86 1.94/1.50 76cc 10065203 350 82-86 1.94/1.50 76cc 10065204 350 82-86 1.94/1.50 76cc 10065205 305 82-86 1.84/1.50 58cc 10065206 350 82-86 1.94/1.50 76cc 10065207 305 […]"487" - 3973487, OR 3973487X. The regular casting was found on the 1971-1972 350 LT-1 engines, had 1.94/1.50" valves, 76CC combustion chambers, DO have accessory holes, intake port volume should be 161CC's, exhaust port volume should be 65CC's. The 487X had 2.02/1.60" valves. "441" - 3932441. This head was found on the 1969-1970 350 engines ...Summit Racing SUM-152123 - Summit Racing™ Cast Iron Cylinder Heads for Small Chevy. Cylinder Head, Cast Iron, Assembled, 72cc Chamber, 165cc Intake Runner, Chevy, 302, 327, 350, 400, Each. Part Number: SUM-152123. ( 112 ) Estimated Ship Date: 3/23/2022 (if ordered today) Free Shipping. Only GM OEM heads. numbers are: 14079267, 3986336, 3986339, 3986339X, 3986388, 3932441, 376445, 3928454, 3932454, 3876487, 3973487, 3973487X, 3973493, 3951598, 468642, 330862, 333882, 3998920, 3998991, 3998993, 3998997, 3970126 or may use Engine Quest (EQ) Stock Replacement (SR) cylinder head, part number CH350I, head must remain as produced ...Small block chevy head castings; Casting # Combustion Chamber size CCs Intake valve Exhaust valve Production Years Misc Engine; 10033867: 62cc: 2.02: 1.60: over the counter 23 degree, angle plug, 196 cc intake runner, AluminumBlock Casting Number. CASTING#.....SIZE...YEAR...MAIN CAP BOLTS....NOTES. 140029.....350...80-84...2 330817.....400...72-80...2 355909.....262.....75....2RT head. 3973487X date K 3 1. LT head. 3973487x date k 4 1. Manifold 6263751 Rochester Q jet 17054927 Front pad. V11 I 6 TDG the manifold gives it away. Its a 200hp 350, I can reach the block number. I could use some help with the engine number on the front pad. thanksJan 10, 2007 · 3973487X 350 71-72 75cc, larger intake ports 3973493 400 71 76cc 3986316 350 71 Corvette, 76cc 3986336X 350 76cc 3986388 307,350 68-76 3986339 307,350 71 74.5cc 3986339X 307,350 71 74.5cc 3991492 350 70 "Camel Hump" head, LT1, 64cc, straight plug 3991492 71-up Replacement head, 64cc, straight or angle plug A BARE set of Chevy Open Chamber heads - 441, 487 or 993 - with "CNC-UnderCover Porting" which includes our CNC-UnderCover Machining, modifications to the intake ports, exhaust ports, chamber modifications, all the cover-up work, installing and sizing new bronze valve guide liners, machining the valve seats for your size valves and providing air flow numbers for your camshaft selection.i have run many 4416 and had billions of 882s and some 624's and have also done research on GM heads castings. you should do some also. 4416 are a good carb 305 58cc head to use for a 350 to pump up CR, have 1.90's put in them and run them, they work great, maybe port them a little, gasket match the runners, polish the exhausts after removign ...of second or third rod throws. OEM or OEM appearing replacement steel rods only - GM 5.7-inch, 6 inch or GM Vortec rod part number 10108688 allowed. Cap screw allowed. No splayed main caps. Conventional flat tappet cam and lifters only, cannot alter lifter bores. OEM firing order cannot be changed (GM: 1-8-4-3-6-5-7-2). May use oil restrictors.LARGE CHAMBER PRODUCTION "ON CAR" HEADS. "487" - 3973487, OR 3973487X. The regular casting was found on the 1971-1972 350 LT-1 engines, had 1.94/1.50" valves, 76CC combustion chambers, DO have accessory holes, intake port volume should be 161CC's, exhaust port volume should be 65CC's. The 487X had 2.02/1.60" valves.Bought this combo today for my 305 replacement, planning to rebuild. I read the block is 4 bolt 68-79 truck and high perf, heads 68-71 hi perf applications. The heads do have double springs I noticed. You guys think I can get to around 300 hp with these heads or should I still go the vortec...1971 Chevy SB Heads 1971-3973487X - Rebuilt- 300.00 dollars. I have a set of Chevy 1971 Heads #3973487X that have been completely gone thru for sale. Heads have the 1.94 intake valves and 1.50 exhaust valves. Cast dates L-22-1. These heads were boiled, cleaned and magged for cracks. Valve seats were ground stock.3973487X page 98 3973493 page 98 3986316 page 98 3986339 page 99 3993820 page 100 3994026 page 101 3998916 page 102 3998991 page 102 3998993 page 103 3998997 page 103 3999241 page 103 330545 page 10.5 333881 page 105 333882 page 106 336781 page 107 346236 page 107 353049 page -107 354434 page 107 Introduction 85 Casting Number Decoding 86 ...Yes it will. GM. put alot of V8 engines in that year camaro. Where is the oil pressure sensor located on BMW 730 year 1989 e32? On the drivers side corner of the cylinder head.During the last 30 years I have seen 3782461X heads on 1961 Corvettes but 3782461 heads on 1962-1966 Corvettes. The 1971 and most 1972 Corvettes used 3973487 heads but "late" 1972 Corvettes used 3973487X heads. I always thought that the "X" was for experimental type heads but who knows.Thay are all different. Need the year and cylinder head casting # It could be 60cc.65cc,70cc it could be anything. Ask your question again with this info. 1989 Chevy 350 t.b.i I still need the ...13) Camshaft: 1) Hydraulic camshafts only. No pump-up lifters. Must run 0 value lash and rocker nuts must back off ¾ turn before 0 value lash. 2) GM-455 maximum lift at valve, stock 1.5 ratio rockers only no tolerance. 3) Springs… 1.260 OD max, open pressure 275-lbs @ 1.250. 4) No roller cams. 14) Crankshaft & Rods: 1) Stock OEM crankshafts.The Chevy cylinder head casting codes are one of the best ways to identify a Chevy cylinder head. It is usually found on the top of the head in between two valves and the rocker arm studs. Choose Group to View Cylinder Head Codes. Select Cylinder Head Group ALL Head Codes 262, 265, 267 302, 305 or 307 302 Only 327 350 400.of second or third rod throws. OEM or OEM appearing replacement steel rods only - GM 5.7-inch, 6 inch or GM Vortec rod part number 10108688 allowed. Cap screw allowed. No splayed main caps. Conventional flat tappet cam and lifters only, cannot alter lifter bores. OEM firing order cannot be changed (GM: 1-8-4-3-6-5-7-2). May use oil restrictors.1,642 Posts. #2 · Dec 27, 2005. The 487 heads will flow as well as any factory double hump head. The only real problem with them is that they have poor combustion and burn characteristics compared to the earlier closed chamber style heads. You can get 220 CFM out of them without too much work and they will make a good cheap set of heads.Sep 09, 2009 · 3973487X 1972 350 165, 175 1.94/1.50 75.47 Used only in late 1972 and overlapped production with #3998993. ... Chevrolet Production GM LT1 372 Aluminum Head 170/214 . Nov 25, 2009 · The LT-1 came with a 041 291, 292, 041, 186 or 187 casting number as they were 11-1 engines as well as the Z-302 engine in that era. The 10-1 engines also used the same castings. The L-82 vette used the 487 and487X heads but lower comp.8.5-9.Thatsaid they would not have been factory installed in a 67 camaro. Thay are all different. Need the year and cylinder head casting # It could be 60cc.65cc,70cc it could be anything. Ask your question again with this info. 1989 Chevy 350 t.b.i I still need the ...Chevrolet 3973487x Cylinder Heads. Dated C 18 2 (March 18, 1972). Used on various Chevrolet vehicles including Corvettes an Camaros. Perfect for use in a late 1972 or early 1973 vehicle or use in your own project. Appears that one head is already cut for 2.02/1.60 valves, the other is cut for small valves (obviously, it will have to be cut for the larger valves).