Thread: Vette motor heads

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I bought a used (ready to rebuild) SB 350 out of a 1974 vette, How can I tell what heads are on this motor and if they are worth keeping, and using once I have them rebuilt?

Thanks Bo

Post the casting number on here. It can be found by removing either valve cover and reading the number.

Number are a follows,

13882 on one and 14882 on the other Thanks for your help, will this also tell the compression ratio? Bo

Casting numbers are either 6, 7 or 8 digits for Chevy SB heads....1981 was
the last 6 digit casting number for a small block.

The casting will dictate the combustion chamber volume from which a person can calculate the Compresson Ratio....if they know a couple of other tidbits.

The casting number is located between the rocker pedestals, usually between the second and third from one end.

the 882 castings are fair they are 76c combustion chamber with a 1.94 intake valve but for the price of work and odds and ends u cant go wrong with the vortec heads lot btter design

Isn't that one of the years that the vette heads were so prone to developing cracks between the valve seats?? Not sure, I do remember a machinist buddy of mine telling about all the cracked ones he'd seen, thought it was the '74 thru '79 or someplace in there????

I bought '76 Corvette 350 to rebuild and it has the 882 heads which seem to be the lowest form of performance head according to flow measurements. See

http://chevyhiperformance.com/techarticles/41598/

I had my heads rebuilt with a three angle valve job and the heads planed down to a 73 cc volume along with a professional smoothing of the exhaust ports. After all was said and done I spent about $500 on the heads so in hindsight it probably would have been better to buy new Vortec heads for about $550, but I will run what I have for while. If you are going to upgrade the intake anyway it is no big deal to buy the intake for the Vortec heads. My question to other folks on the forum is what was the most restrictive part of the low HP numbers of the '74-'76 Corvette 350s? I have the lowest of the lowest originally rated at 160 HP with a two-bolt main block, but even the four-bolt block only put out about 210 HP. If the 882 heads flow well at low rpm what is the choke condition on the rest of the engine, the EGR intake? The original Rochester Quadrajet was rated at 750 cfm (I think) so that should not have been the restriction. What about the cam? Maybe the main problem was the detuned cam? I am using only a Crane blueprint of the 300 HP cam (flywheel) from the earlier 350 and I am hoping for low rpm torque for the OD trans at low rpm but hopefully more than 160 HP! Anyway from the flow data at the site given above the problem is not at the head ports so maybe with a better cam you can improve that Corvette 350. If you check out the Chilton's listing of the HP numbers for the Corvette from '70 to '80 you will be amazed at how detuned the 350 was. I was also very disappointed with the cheezy plain tin valve covers on my two-bolt 350 but I'll live with slightly less cheezy chromed tin covers!

Don Shillady
Retired Scientist/teen rodder

I am running a 327 v8 with the 202 heads and it was pushing 365 hp...factory numbers. the 202 heads are a great deal and you can find them in great shape for not much money at most swap meets. I believe they are also referred to as "350 double humps heads" because of the "double hump" on each end of the head created in the manufacturing process. I would assume you could find a pair in really good shape for under 300 bucks and that would significantly help hp. then get them port and polished and you are even further along.

I have seen the edelbrocK head, cam, carb, and manifold deal for about $1600 seems like anaffordable way to 410 HP

yes chesapeake has the right idea but if you have every thing else than the vortec is a great design. gm did their home work these heads. and if you do any work to those 882 heads get prices and compare. the vortecs are ready to go out of the box

All I have is the stock motor,, what cam carb, Manifold would you recomend? Thanks Bo

on a stock motor hmmm. cam extreme energy 268 no bigger than a 750 carb and prolly an rpm air gap for an intake and i would assume that since you say stock that the original timing chain is still there change it

383, thanks. I have a Performer manifold, new timing chain, Z28 springs (which don't mean much with a little cam), 1.5 roller rockers for breakin and then use 1.6 roller tipped rockers and hoping to get an honest 250 HP at about 3500 rpm with only an Edelbrock 600 cfm carb and shorty tube headers. Gee whiz what did they do to that '76 350?

Don Shillady
Retired Scientist/teen rodder