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| | | Forums66 Topics128,012 Posts1,055,312 Members48,419 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: May 2004 Posts: 7 Junior Member | | Junior Member Joined: May 2004 Posts: 7 | A few months ago I purchased a Chevy pickup in which the previous owner had changed engines. I trying to identify exactly what I have before tearing it down for a repair. The owner said it was out of a 76 Chevelle, but much of what he said has proven to be untrue. The numbers on the front engine pad are TO623CRX, the C could be an O, but looks more like a C. The numbers cast into the cylinder head are 333882 also a seperate number F18 space 76 or 75 I can't be sure but I think 76. The heads may not be origional to the block, as they are panted a different color than the block. Thank you , I hope someone can help. I have to pull the haeds at least, as It appears the previous owner misadjusted the valves and ran it that way burning some valves.
John
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | the heads are from a 350ci, 72 up [june 18, 75 or 76?] so could be 76 chevelle 350 that number from the pad needs a engine prod list book and indicates exactly what the application was and what equipment was originally on it, if someone has the book they could decipher it, but there'll be a number cast on the block that'll show what the block is and date too - no doubt 350!
Bill | | | | | Joined: May 2004 Posts: 7 Junior Member | | Junior Member Joined: May 2004 Posts: 7 | Bill, I appreciate your getting back to me so quickly. There are some numbers cast into the block back by the bell housing, but I am unable to make them out with the engine in place. Thanks again. John
John
| | | | | Joined: Dec 2004 Posts: 452 Member | | Member Joined: Dec 2004 Posts: 452 | The CRX suffix was used on two versions of the 350 in 1975--a 4bbl, 155hp version for Chevelles and Impalas/Caprices, and a 2bbl, 145hp version for Camaros and Novas. My source for this info is here.
Curt ---- 1953 Chevy 6400, 1957 Chevy 2dr Sedan --"Mediocrity is easy, the good things take time"
| | | | | Joined: May 2004 Posts: 7 Junior Member | | Junior Member Joined: May 2004 Posts: 7 | Those web sites are a big help. I just added them to my favorites. Thanks again John
John
| | | | | Joined: Aug 2004 Posts: 1,067 Shop Shark | | Shop Shark Joined: Aug 2004 Posts: 1,067 | The good news is, all you need is a set of Vortec heads for about $500 bucks and a more modern cam to more than double your horsepower. Those heads you have are low performance, low compression heads and basically they suck.
If you do go the Vortec route, then I would recommend the Edelbrock RPM Air Gap Vortec manifold for max power. Or if you want the heat risers functional, then get the Performer RPM without the air gap feature. Power is only incrementally lower than the air gap.
52 GMC 3/4 ton pickup 68 Big Block Vette 68 455 Firebird | | | | | Joined: Feb 2004 Posts: 29,743 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,743 | I scavenge up all those "junk" low-compression heads my friends throw away, and then beat them at the race track with their own junk! A .100" angle-mill job and a set of big valves turns it into a 60CC high-compression head that will run rings around their high-dollar "Camel Hump" heads! The nice part is, they still have the low compression casting numbers, and most tech inspectors aren't sharp enough to spot the angle-mill job! Great for "claimer" engines that look stock! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Nov 2004 Posts: 122 Member | | Member Joined: Nov 2004 Posts: 122 | hey John, where did you find the casting numbers? I've been looking for my casting numbers on my '68 school bus smallblock for a while and cant find them under the gunk. it's an unoriginal chevy smallblock claimed to be a 305 but I dont know for sure | | |
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