72and86

Im looking to replace the heads on my L48 1975. I can buy some "Heads 64 cc Chambers These are the desirable 3947041X castings." I know absolutely nothing about heads. What are the considerations putting those on my 75? Or are there better choices? Thanks

F22

The L98 Aluminum heads off've the 4th Gen Corvettes have a 58cc combustion chamber and will bump up the compression by a good amount. Add an RV-4x4-Marine cam like the Lunati Voodoo cam with a lot of torque, a regular Edelbrock Performer and headers and you will have a lot of fun. I built an L48 like this for my '74. This combination, with a four speed, did low 14's at the drag strip. A good two seconds faster than stock.

4-vettes

There are lots and lots of choices for your L48.
64cc combustion chamber size is fairly common amongst many brands.
Your choice will come down to budget and what other changes you are doing to this engine.
Basically, any aluminium head with 64 cc chambers will be an improvement over stock. Runner size is also important.
What are you building? Or simply replacing heads?

stingr69

The "041" heads are some of the best of the factory heads but any aftermarket head will work much better. They are equivalent to "double hump" castings but nobody wants these 041's because they just have no restoration use value. If the "041"'s were already rebuilt and very cheap you could run them. Usually, the cost to buy them, plus the cost to rebuild them will exceed the cost of a set of brand new aftermarket heads. The "041"'s in most cases just don't make any sense. They are limited to about 300 HP max in the common smaller valve versions.

Do you have a budget in mind for heads?

Rescue Rogers

save your money adn go with an aluminum head...even a GM vortec head will be a better choice....whats your budget and when looking at Summit make sure you know you are buying individually or a pair

lars

Those are the standard 300-horse 1.94 intake iron heads for 1968-70. Nothing special about them at all unless you're doing a "numbers" restoration on a 68-70 with the right date codes. You'll wrap up more money rebuilding those heads than what you would pay for a nice set of well-flowing aftermarket aluminum heads. Total waste of time and money getting those heads - you'll raise your compression but do nothing for flow, so the performance increase would probably not be noticeable. I have flow tested the 3947041 versus the "X" heads, and there is no difference at all between the "X" and "non-X" heads - they flow as poorly as any other stock, iron 1969 head.

Lars

72and86

Engine is in the car, just replacing the heads. My mechanic buddy says the car really needs a valve job so I figured replacing the heads in a '75 might be a good idea. On a tight budget since it needs some paint work too...

72and86

Good advice. On a tight budget since it needs some paint work too...

72and86

On a tight budget since it needs some paint work too...

72and86

Good advice! Thx man!