I have a GM perf parts zz4 350 crate motor in my 86 Iroc. It has aluminum heads and intake both ported and polished. I'd like to get a little bit more power out of the motor and want to upgrade the cam. Any suggestions?

Thanks!

 

How much lift can your heads support

 

not sure. The cylinder heads are the aluminum heads that come with the zz4 crate motor. I currently have what came with the crate motor...a Hydraulic roller tappet pn# 10185071 .474''/.510'' lift and 208/221 degrees @.050'' The valves are 1.94'' intake and 1.50'' exhaust with a rocker arm ratio 1.5:1 I do not know how much the heads can handle nor know how to figure that out. If anyone else knows, please chime in. Thanks

 

Yes, with the springs on those heads you're limited to about .525" lift, max.

 

I would like to assume that if you can put this motor in your 86 iroc i should be able to put it in my 91 rs originally equipped with the 305 tbi. Does anyone know? I have been reading until my eyes are starting to bulge outta my head....I may have found what i believe to be a decent deal on one.

 

you have a GTO... and its beautiful.. good taste sir

 

Not only is it beautiful, its got mods and fast as a mother f&^%#r. Thanks! But that doesnt answer my question...

 

LT4 Hot cam or CC503 cam, kept both with 1.5 rockers, as I'm not sure how high those heads can go but i know they are capable of more lift than stock L98 aluminums which are same type of head.

You carbed or TPI. If TPI, zz4 cam isnt bad choice. Go no bigger than LT4 hotcam. ZZ9 is good for TPI.

 

i'm carbed