I'm in the middle of an engine swap (350->385) and during final assembly I ran into an issue where the center bolt holes on the older rebuilt heads I'm using don't match well with the TPI intake holes.

The issue is that while the holes line up fine, the angle of the intake hole is more vertical than what the heads are.

Any idea if there is a way to adapt the intake to fit?

I found this article and this article which basically says to just drill proper holes, so if anyone has done this, then is just as simple as making the holes a little wider and maybe counter-sinking on top for a better bolthead to intake mating?

Thx

 

Apparently you have an '87-later TPI base. '86-earlier and Corvette TPI base had all of the bolt holes at the same angle. Your choices are to trade your base for the other type, or elongate the holes in your base so you can get the bolts in.

I haven't done it myself, but sticking a 3/8" drill bit in the hole and running it until you get the correct angle makes sense to me. I've heard machine shops will do the job for you as well. Just doing that won't give your bolt heads a flat surface to clamp to, fixed either by getting angled washers to put under the bolt heads (I couldn't give you a source for them, I've heard some aftermarket intakes include them), or having the machine shop put the surface on for you.

No matter which way you go, most likely the base will have to be off the engine to fix the issue.

 

How did the modification work out for you? I have the same issue.