I have a good running '88 305 roller-cam SBC that I'm planning on putting in my low-budget old work truck. A friend has offered me a set of '85 Corvette 350ci heads he replaced on another engine. I was going to have the 305 heads checked out for a possible valve job. Should/could I bring the 350 heads to the machine shop and use them instead? Would they work and what advantage would I get if that, headers and a Holley 600 are all that is done to the 305? I know there are those who will say don't use a 305, but it is free and in good shape and I only want to replace a worn out 6 in the shop truck, so please advise me on this budget project. Incidentally, the 305 is a roller rocker engine and the 350 was not. Thanks
You need to find out the chamber size on the vette heads. May drop your compession quite a bit, sounds like a budget - prts on hand build. Nothing preventing you from bolting them on, consider the ex manifold bolt pattern may be different than the 88 engne, but you're running headers. Watch your distributor gear with the roller cam, use a compatible gear. Dual plane manifold with 600 holley or q jet.
350 heads on a 305 yeild about a 2 point loss of compression ratio. Not too helpful as a performance up grade.
The TBI issue is pretty easy work around. The valves are probably going to require clearance in the cylinder walls. The loss of compression is going to really hurt . Lots of work for less power.
I'd check the comb. chamber. I think 305 have alot smaller ones. this would drop. the compression ratio. and sometime in the 80's the center bolts for the intake change angles. check this too.
TBI- yes. Cast iron heads though on the original L98 in '85. Didn't get the al heads until either later in 85 or in 1986.
I rebuilt my 350 with a set of 305 heads this summer. gave the 350 a nice boost in compression on the cheap. I think there may be some interferance issues the other way around with valves.
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