Throttle body
 

If you were building a 1990-1992 Chevy 350 (245/275) for Stock or Super Stock, utilizing the NHRA Engine Blueprint Specification Guideline and Stock Car Classification guidelines, what throttle body would you "legally" use?

Re: Throttle body
 

In the blueprint specs all the way to the right of the engine choice depending on year you will see either a number 1 or 2....go to the bottom and it says that the 2 x 1.889" (48 mm ) throttle body is the legal one..........D L Rambo...STK 1300

Re: Throttle body
 

I was told quite recently that OEM throttle bodies only in stock and super stock. I was asking if specs say 80 mm, can I use any. Answer was no. Just sayin.

Re: Throttle body
 

As far as I know all the GM 2 port throttle bodies are more of less the same spec. The publish size is in the blue print specs. Some of the TB have slightly different throttle attachments.

Re: Throttle body
 

There are generally only two TBI sizes. One is a 1 11/16" bore that is used on 4.2, 5.0 and 5.7 engines and the other is a 2" bore used on 454 engines.


Sorry! I pulled the trigger to quickly. I thought you were talking about TBI engines.

Re: Throttle body
 

The spec sheet does not list a part number, all it has is N/A. In the notes it says 2 @ 1.889 48MM, so I guess you can build your own throttle body just make sure its 48MM