I've got a set of 1956 Corvette heads with casting number 3731762. I was wanting to use them on a SBC. I need a head that has the early style valve cover bolt pattern for a period correct application. Are these heads better than any others? Value of the heads?
Don't know much about the heads but i've got a set of the right finned alum valve covers for them, give me a shout if you need em. oj
For what you could get for those heads from someone that's redoing a '56 'vette, you could buy a pair of rebuilt '57 power pack heads (bigger ports than '56, but still staggered valve cover bolt pattern) and have change left over.
Yes...I remember a query in HRM's letter column long ago about reworking some of these. The reply, probably Racer Brown or Don Francisco, was advice to keep the hardware and buy a set of '57 castings. Editor said that no possible rework of a '56 head would work as well as a stock '57... There were quantum leaps in Chevy ports in '57 and then about "63.
Ebay will probably get you the most money. Just list them with a good description and use the html format to load up "free" pics!
Can you post a picture of the end of the head? It would be insightful to see what casting marks these (probably rare) Corvette SBC heads have on the ends.
corvette weenies as well as 56 chevy restorers are all about casting dates. I had a standard bore 56 265 I had a hard timer giving away. I had several inquiries and all asked about the date.
They only came on a '56 2x4 car and Corvette and have a unique double bar casting mark on the end of the head. Pretty rare. About 10 years ago I had a pair of '57 2x4 (and 250hp fuelie) heads, that have the unique single bar casting mark. I sold them back then for $1,800. I have a pair of real rare '57 283hp fuelie heads that have their own casting #, 3731539, but the triangle casting mark looks just like a PowerPac head. 'Cause of that, they won't bring the $dough$ of the others. I'd sell them to a restorer or run them as is. Don't port them
Good Info modifieddriver. Thanks! Are the cumbustion chambers on either the single bar '57 or the double bar '56 heads unusually small? What size are they? Anybody have any extra '57 Corvette fuelie head that they want to get rid of (539 casting that modifieddriver talks about above)? My friend gave me one a couple of weeks ago, but he couldn't find its mate.
When the Lazy 8 was orginally built, Jim went to GM and purchased one of these 56 265 vette motors over the counter. With some porting and a Giovanni cam the car ran 12 flat back in 57-58! The motor was still intact when my dad sold the car in 75. This summer, I found the guy that pulled the motor out in 1980! I purchased it back from him. Unfortunatly, he got the motor to sell the heads. Back in the early 80's they brought $2000! I would love to have your heads, but not at that kind of money, I plan to run the 57 power pack heads if I can find a set. Don
57 FI heads (539) for the 283hp 283 were the same casting as the 1957 Chevrolet Passenger Car 283 four barrel engine (220hp 283).
I have a pair of the Corvette Fuelie heads- ran them through e-bay last month but didn't hook up with just the right Corvette guy that wanted the dates cast in my pair of heads.
The big money lies in the 3740997 for 57'. Power Pak heads=Easy to find. 1539 57' F.I., Truck,or 4bc=little tougher. "997"=much harder to find and big $$$.
'56 "306" Powerpack, '56 "762" (2x4bbl) heads, and the super-expensive '57 "997" (2x4bbl) heads all share the same combustion chamber, which is smaller than the rest of the '57-up Powerpack heads. The valves are shrouded a lot more in these heads...the chambers are probably about 60cc. I have a pair of "306" castings, and they have noticeably smaller chambers than my '57 '539' heads. We cc'ed the chambers on my '57 "539" Fuelie heads and I was shocked to find out that they were 64cc. As far as '57 heads go, the "997" heads bring stupid money, but the easier to find "539" and "539x" heads have a better combustion chamber, and any diference in port size and shape is probably marginal at best. If you are wanting to use an early head for anything other than a resto, you'd be better off selling the "762" heads and starting with a '57 or later Powerpack head, as mentioned above.
If you don't care about staggered or straight valve cover bolts I would use 520 castings. They have small combustion chambers and were used but racers at the Drags in Stock Eliminator. Bob
You could use any head, just braze some 1/4-20 nuts in the right place, and the casting for powerpack remained the same till they started putting bolt holes in the end of the head, in '68?
OK, here are some pics. One shows the combustion chamber, which I had cc'd at 56. The other shows the twin tower end casting. The last is the casting number. Dan Marvin, Owner Exeter Auto Supply
Here is what has me confused. The casting date on one head is E219, the other is E259. Unless the "6" has been reversed, that would mean the casting was on May 21, 1959 for one head and May 25, 1959 for the other head. If I assume that the "6" was reversed than the day would stay the same and the casting year would be 1956. May 21, 1956 was a Monday and May 25, 1956 was on a Saturday. Did GM run the plants on Saturday? Dan Marvin, Owner Exeter Auto Supply
Weekend overtime is a lot older than the 50s. Casting dates are just that, casting dates. Not the date it was machined, or assembled onto an engine. Castings are produced by lot in the foundry, then shipped elsewhere for finishing. 4 Days apart at the foundry should indicate a pair that have been matched since 1956.
Put them up for sale on the C1/C2 section of corvetteforum.com, as mentioned before, you shuold get a good price for them.
Googled the part number from your first post and this was one of the results. It's from 8-23 so he may have found what he wants already...but it might be worth a try if you want to sell them. http://www.corvetteactioncenter.com/forums/showthread.php?t=107369
Found this too. From Feb 08 so, again, may have already filled the need but may be worth a shot. http://forums.corvetteforum.com/showthread.php?t=1936074