Questions about IROC heads

[KaosMan]

I'm currently putting a 350 from a '92 Caprice into a '92 Toy 4x4. A friend of mine has a set of heads from a '86 IROC that he used to own. He's pretty sure that its a 305 but can't remember what he had in it.

So, are the heads compatible between 305 and 350? And will they give me any performance benefits over the stock Caprice 350 heads?

[tom3]

See some problems with this. The 305 heads have very small chambers, boost compression a point or so, but small valves and ports. Lot of low end grunt but no horsepower on top. Also the early heads bolted to the intake different than the newer engines. Might want to look close at this before starting on it.

[hardcoresoldier]

the engine in that caprice should be an lt-1 so the heads will not even bolt on.

[chris89gta]

Originally posted by hardcoresoldier
the engine in that caprice should be an lt-1 so the heads will not even bolt on.

LT1s were only in the Vette's in 92. They didn't start putting those motors in other cars until 93...

[hardcoresoldier]

my bad.im blamin the mistake on the anthrax shots im gettin here in iraq.

[MonteC]

Originally posted by tom3
See some problems with this. The 305 heads have very small chambers, boost compression a point or so, but small valves and ports. Lot of low end grunt but no horsepower on top. Also the early heads bolted to the intake different than the newer engines. Might want to look close at this before starting on it.

:stupid:

there really more of a restriction than anything.

[Stingray]

KAOSMAN you want heads go Vortec. Best bang for the buck. I installed them on my Vortec 409. Haven't fired it yet but the dyno says 480 pounds of torque & 420 horses!