Can anyone explain to me or send me to a site that tells which TPI runners goes where? Are there other differences besides the fifth tube? Mine is blocked off at the top, Why? Can I check part #'s somewhere? Thanks, Mike

 

What year is your car? The 5th tube was used on 85-88 models for the ninth injector for cold start. Starting in 1989, GM changed the programming in the ecm to enrichen the mixture for cold start by changing the length of time the injectors were open during cold weather start up. If you have the later model car and want to use an old style runner, you just block off the extra tube.

 

I do not have the matching car, but the block and heads are from a 80-85 model 305. The TPI unit appears to be a 85-88 model with the cold start injector. Are the runners compatible with 89-92 runners? My 5th Runner Is blocked off but has the 9th injector hole in it, should I drill it out and get a passenger side runner?

 

I'm not sure Mike. You might give Don a p.m. and ask him.

 

Who is Don?

 

Dyno Don on the board, Mike.

 

Does your car have a MAF sensor?

If not, it sounds like your MAF engine might have been converted to a MAP car, thus the 9th injector eliminated.

 

It is a MAP setup from Accel. So I guess I should just leave it alone?

 

Yes