I wouldn't have posted this if I found the answer, but I couldn't, so I thought I'd ask.

I read a long while back about there being a possible conflict with the stock throttle body bolts not threading into the HSR because one was metric and the other was english, although this varied from year to year or something, so its not a common problem.

I've got a 92 TPI, and was wondering if I could expect that problem, and if so, what is the correct bolt (diameter, thread #, and length) to install the TB to the HSR?

Thanks guys.

 

Stock bolts fit fine.

 

the tb bracket bolts were a different threading than the stock bolts on the hsr's i've installed.

 

On a 1990 plenum, they went in fine. Then when I installed my nitrous plate, the bolts supplied were the same thread but longer... also went in fine.

Maybe GM switched the threads or something over the years.

 

doubtful GM changed the bolts..... perhaps holley changed things around. just like different revisons of the HSR. that's more believeable?

 

My TB bolts fit fine... I had to get 3 new bolts for where the throttle CABLES attach to the plenum.

These bolts have bolted to an '85 TPI plneum, '87 TPI plenum, and now the HSR.

 

I've got a 92....has anybody installed a 90+ TB on the HSR without problems?

 

Yes.

 

Sweet.

What did you use for a wateneck? I read a guy said he used his stock 92 just fine, but looking at my car it seems impossible.

Also, I've read a lot that the Mr Gasket one warps and is useless. What did you do?

 

I currently have the warped and useless Mr Casket.... complete with water stains under it.

 

Figures.

What are you going to try now?

 

use the water neck off a 305 tbi motor. get it from the salvage yard. the parts stores stock the one with all the "holes" on top of it. i then used a 86' carb upper radiatior hose. it works fine and looks stock.