Changes for TPI?

[wako29]

I have a TPI system (off a '86 Trans-Am, so am assuming that the TPI is '86, but the motor is different-or at least rebuilt-so I really dunno for sure) and everytime I try to find parts, the majority of them are for '89-'92 TPIs. What were the differences?

BTW, I am putting the intake on a brand new 350 crate motor (nothing really special) and into a '86 Caprice Classic, so I dunno if that means anything for getting parts.

[wako29]

oh, come on

nobody knows? Not even a linky?

[N20LT4Bird]

I had an 88 TPI 350 and i dont ever remember there being a break at 89 to something different. I know that some of the TPI's were speed density after 88. Maybe thats the issue??

[WICKED LT1]

Re: Changes for TPI?

Originally posted by wako29
I have a TPI system (off a '86 Trans-Am, so am assuming that the TPI is '86, but the motor is different-or at least rebuilt-so I really dunno for sure) and everytime I try to find parts, the majority of them are for '89-'92 TPIs. What were the differences?

BTW, I am putting the intake on a brand new 350 crate motor (nothing really special) and into a '86 Caprice Classic, so I dunno if that means anything for getting parts.

There are 3 different TPI's that were used in the 3rd gens. The first, I believe it's 85-88, used a MAF and had a cold start injector (9 injectors, 8 cyl inj, and 1 in the manifold to enrich the mix for when cold.) The 89 was a MAF w/o a cold start inj. They used the ecm tables to enrich the mix. The 90-92 was a pure speed-density system w/o cold start. There are numerous ways to tell the difference, check out on the net. Also, there were a lot of differences in ECM's for these too. The 85's used a unique ECM than the rest. Also, you can usually convert the older units to the newer setup if that's what you want. Check my dates, because I may be a year or so off, it's been awhile since I was in 3rd gen land. :-)


-Paul

[wako29]

Re: Re: Changes for TPI?

Originally posted by WICKED LT1
There are 3 different TPI's that were used in the 3rd gens. The first, I believe it's 85-88, used a MAF and had a cold start injector (9 injectors, 8 cyl inj, and 1 in the manifold to enrich the mix for when cold.) The 89 was a MAF w/o a cold start inj. They used the ecm tables to enrich the mix. The 90-92 was a pure speed-density system w/o cold start. There are numerous ways to tell the difference, check out on the net. Also, there were a lot of differences in ECM's for these too. The 85's used a unique ECM than the rest. Also, you can usually convert the older units to the newer setup if that's what you want. Check my dates, because I may be a year or so off, it's been awhile since I was in 3rd gen land. :-)


-Paul

good advice, but am looking more into it

also, I thought that 3rd gens were LS1/LS6

[WICKED LT1]

Re: Re: Re: Changes for TPI?

Originally posted by wako29
good advice, but am looking more into it

also, I thought that 3rd gens were LS1/LS6

3rd Gen cars were available from 82-92 and were equipped with TPI (L98 and LB9? 305) Engines as well as a LO3 305TBI, and a V-6.

4th Gen 93-97 were LT1 and 98-02 were LS1. No F-Body ever came equipped with an LS6. Only the ZO6 Vette. The 00-02 F-Cars had the LS6 intake, but that's all.

HTH

-Paul

[Danimal]

Don’t forget the intake manifold changed bolt patterns in 89. The four center bolts are at an angle different from the rest. This was for the TBI engines but they all used the same heads so the TPI engines got them too. And with the center bolt valve covers.

[WICKED LT1]

Originally posted by Danimal
Don’t forget the intake manifold changed bolt patterns in 89. The four center bolts are at an angle different from the rest. This was for the TBI engines but they all used the same heads so the TPI engines got them too. And with the center bolt valve covers.

Good point. I had forgot about that. I try not to think about the 80's unless I have to :-)


-Paul