head question

[bananaMC]

I got a weird question. if i put 305 camaro heads on a 350 truck motor will it raise my compression ratio? block is 75 truck, heads are 89 camaro. the motor with a 700r4 from said camaro is going in an 86 toyota pickup. gotta love the projects

 

[ss4ever]

Your compression will go up a bunch and you will have problems with pre-ignition(spark knock) not to mention the small valves will restrict flow and the engine will not perform as expected.


Randy

 

[Chevyman85]

Your compression will go up a bunch and you will have problems with pre-ignition(spark knock) not to mention the small valves will restrict flow and the engine will not perform as expected.


Randy

I have to agree. You would be going to a smaller combustion chamber thus upping the compression ratio in the process. By doing this you would have to run higher octane fuel. Not only that but you would have to deal with detonation and hot spots in the pistons. I would recommend having the heads you have now machined, or getting a set of aftermarket ones. You'd be saving yourself the trouble of doing it twice.

 

[bananaMC]

thanks a bunch. I would thinka camaro head would flow much better than an old pickup. but thats why i asked. I also thought most pre 85 heads would fit any block as long as they were sbc. didn't know how many cubes mattered.

 

[383Camino]

I agree with them. I know a guy with a square S10 with a 350. He had 305 heads machined for 2.02 valves. It has a 650 Holley and TH350 with 3.42 gears. Not sure on the rest of it. Best time was 13.40s on drag radials. Just some food for thought.

 

[FLY_THE_BOWTIE]

thanks a bunch. I would thinka camaro head would flow much better than an old pickup. but thats why i asked. I also thought most pre 85 heads would fit any block as long as they were sbc. didn't know how many cubes mattered.

best flowing heads gm made until the vortex was off late 70s trucks, last 3 casting #s, 487,487x,993,882,. these heads all have 1.94/1.50 valves and 76 cc chambers.they dont help comp much but work very nice with a decent cam. also the heads can be shaved for a little more compression and you can run a cam that will increase cylinder pressure.

 

[ONE EYE]

i had some 882's that had 2.02's factory, so you may run across a set like that.