I need help finishing my all forged 383 stroker that im putting in my 88' iroc-z. I have the block compleated aside from transfering the serpintine system onto the new motor. Where i need help is trying to find out if the cam and heads i put together will work on a prom, what size injectors i need, and if i should expect any other problems along the way. The specs on the cam are 290/300 adv duration, 222/230 @.050, .468/.480 with 1.5 rockers, 110lsa.... It has 1.6 rockers so the lift is actually .499/.512 at the valve. The heads are 1.94/1.6 valve size and are older small block heads. The compression is 10.5:1. I know i want to delete the smog/air system, will need to drill a hole for the 88 tpi to fit the older heads, and plan to add header into x-pipe/cutouts/flowmaster. If you see any mistakes or have some advice it would help me out alot, this is my 1st swap. Thank you for your help

Brandon

 

What exact heads are they?
You'll want to make sure you can clear .520" or so lift, safely. Rig up a tool to compress your valve .570" or so (.050" safety), and make sure you aren't hitting the retainers against the valve guides, or getting the valve springs solid.
What cam is that? Seems like a very slow ramp, 290/222?

That compression ratio might be a tad high for those iron heads.

You'll just need to wallow out (ovalize) a few of the holes in your TPI manifold in order to match up with the bolt pattern on the older heads. You'll know what I mean when you go to bolt it up and go . Then you can fix it easily with a die grinder.

 

I have to agree. That is one lazy cam.

 

So would i need a new cam? The heads are the older gm heads that went through 86 (reconditioned). I want to push as much HP as i can and it still get decient gas milage. The guy from tpichips.com said this setup would have trouble working with a chip and suggested ( comp cams 8-465-8)

 

geez man, give us more info than a part #, how about the specs?
grumble grumble, make me go look for it...

260XFIHR13
210/218 260/270
.560" / .555" (with 1.6 rockers) 113LSA

Yes, i'd agree, that cam would be MUCH better for what you're trying to do. But 210/218 is quite small for a 383, i'd look at the one step up, xfi268 which is part # 08-466-8

I have no idea what those heads are unless you get a casting number off it. But 10.5:1 on iron heads, with that small of a cam is kinda sketchy. TPI helps a bit, but i'm still kinda leery. You've got to have perfect quench, and use 94 octane if you can find it.

 

Right, mucho better cams. Your heads may need some work in order to get the valve lift the cam needs. However you will be way ahead.

 

The LSA on every roller cam i have found is 110. Will the setup i have now work @ all? I was told aluminum heads would not work well with a cast iron block because the aluminum expands more in heat causing leaks. Is it better to have aluminum heads besides the weight? Wouldn't that cam be more of a prostreet cam? Again i am still learning so i don't mean to critacise. Do you know what size injectors i may need?

 

AL heads do expand at a different rate than iron heads, but that's not as big of a deal as most people think. Many cars had AL heads from the factory, with an iron block, and many more people use them as an aftermarket addon to their cars - with no leak problems.

Yea, AL heads also dissipate heat faster, so they let you get away with a higher CR.

What cam is more of a pro-street cam? The one you have or the one I mentioned? All the cams listed are perfectly driveable daily driver type cams. I have a cam very similar to the one I listed, a 268 cam, and I would daily drive my car (if I didn't keep breaking driveline parts).

I think 1989GTATransAm has the exact cam I listed, and did pretty well on the dyno.

Just to make sure, you're looking for a roller cam right? Not a flat tappet? I just realized I never asked...