I was wondering if the TPI intake from a 86 Firebird would fit my 87 firebird, I heard they are all pretty much the same, please let me know what you guys think! Also is the intake the same for a 305 and a 350?

 

They are essentially the same, except for the angle of the center two bolts on either side of the intake where the intake flange bolts to the heads. The newer heads use bolt holes that are not perpendicular to the head intake flanges, so the intake is drilled to match.

 

How big of a deal would it be to drill it out? Could it be done easily? Will it pose any problems with vacume leaks or anything?

 

Very easy to drill. Nothing to leak there except the EGR & exhaust heat crossover. Many people block that off anyway.

 

It's probably just as easy, and a cleaner job to file the four bolt holes in the intake to provide bolt clearance. The only remaining issue is that the bolt heads will not seat on the intake flange correctly. You can get 15° tapered washers (structural steel washers) or use self-centering washer sets if you can find them. McMaster has the sets if you want them by mail.