I need to get a set of sbc heads. I bought a motor off of a guy who was going to convert it to an LT-1. He took the heads and had them ported, and cut for 2.02/1.6 valves, and for bigger springs. I'm not quite sure what size the springs are yet, I'll still have to measure them. The motor also came with a Comp 306 hydraulic roller cam with .340/.361 lift, 7635 Comp Magnum 7.15" pushrods, and a set of 1.6 roller rockers with stud girdles. According to the guy I bought the parts from, the top end has only about 5k miles on it. So I was going to try and reuse all the parts, and just buy bare heads. He had the intake water jackets on the heads blocked off with, what appears to be, aluminum, bc of the LT-1 intake. It looks like the machine shop melted down some aluminum and poured it in the ports somehow. I tried drilling it out, but the stuff is harder than all hell, and it goes in really far. I don't think I can get it all out. My question is, can I take this set up and throw it on a set of heads set up for these valves? Are there different valve stem lengths that I need to worry about for different heads? One set of heads i saw online said that the pushrod guide holes need to be elongated if 1.6 rockers are used. Is this true for all heads? Am I better off just buying a set of assembled heads, and if I do, can I use these pushrods and rocker arms?

 

So what do you actually have ????????
A SBC short block with modified LT1 heads and a LT1 intake?
or a LT1 intake to go on reg SBC heads?????????

There are no coolant to intake holes on a LT1 head ;
are you saying you have reg SBC heads with the coolant holes blocked to match a LT1 intake ?????????????

 

That's exactly what I'm saying. The guy took an L98 from an 89 Trans Am and was going to put an LT-1 intake on it, but failed miserably. Yes, he had the coolant passages blocked off so he could put the LT-1 intake on it. I basically have a sbc with f'd up heads. I have no intake yet, probably going to go with the hsr, and I just got done rebuilding the bottom end with a fresh eagle rotating asm. Now I need to figure out what I want to do for heads, but I was thinking about reusing the springs, valves, rocker arms, and pushrods.

 

Cut your losses and buy new heads. Time you have bare heads worked over and setup with those parts you should have enough money into a new set.

I wouldnt use the parts anyway. Maybe the valves but they need checked and valve jobbed anyway. Springs i would buy new for that cam. Pushrods may not be correct. Will have to measure them

 

How do I know what length my pushrods should be?

 

You gotta mock them up and use a length checker. Some shoot for rocker tip sweep pattern over the center of valve stem. Narrowest sweep pattern as well but it can be slightly off center but not to far off. I had my first valve guide issue this year by doin it this way which was the way i had always done it. Not sure why. Now i will try another method of lining up rocker centerline to valve stem at mid lift. Find the 90 deg angle it makes and thats your pushrod length