1986 tpi 350
 

Bought an engine on the west side of San Antonio yesterday, was told it was a 1987 or 1988 Z/28 350 TPI. When I get there it is a TPI engine but it was different in some ways, perimeter valve covers, no 9th injector, 1 piece rear main 638 block. Fifty dollars later they load it in my truck using a dog leash instead of a chain hung on an engine hoist. So does anybody know about the 86' TPI engines? It has 261 heads. 1986 was a year in transition for the SBC. I haven't pulled the intake yet but could the 638 block be a non-roller block? I have other 638s and they are two bolt main 350s, the 880s are four bolts. I did pull a valve cover and it was very clean like could have been rebuilt clean. Opinions? A pieced together engine?

Re: 1986 tpi 350
 

We used to run one in a SCCA Show Room Stock Camaro . The 350 TunePort was only available with an automatic transmission . Most of the other guys ran 305HO , QuadraJet , engines with a 5 spd manual . Our advantage was using the torque of the engine , and never revved it over 4000 rpm . Got much better fuel economy than the 305 crowd . These were typically 12 or 24 hour races , and you won if you had the most laps .

Re: 1986 tpi 350
 

What year car?

Re: 1986 tpi 350
 

1986

Re: 1986 tpi 350
 

1989 was the first year with no "9th injector".

Re: 1986 tpi 350
 

What is the 9th injector ?

Re: 1986 tpi 350
 

It is used to enrich the mixture during cold starts .

Re: 1986 tpi 350
 

The 350 Tunedport engine did not come out till 1987. In 1986 engine choice in the Z/28 were 305 tunedport or quadrajet. The Players Challenge series Camaro and Firebirds ran with the 305 tunedport setup and 5spds. Clutches and rear brake pads were allways being changed. We got real good/fast at changing them out.

Re: 1986 tpi 350
 

I have been working with TPI engines since 1985. On the 350" only in the Corvettes, 305"s in the Camaro/Firebirds. The 9th injector for cold starts used until 1989. Mass Air Flow sensors used until 1990, first year for Speed Density Mode (MAP sensor used instead of MAF sensor.) MAP stands for Manifold Absolute Pressure, which is Barometer minus Manifold Vacuum. Measures Baro at key-on, before start up, then vacuum/MAP.
Had a lot of 1985 305" Tuned Port Injected Camaros/Firebirds across my dyno.

Re: 1986 tpi 350
 

I got around to taking it apart last night. First I was wrong there is a ninth injector. The block is a 1 piece rear main seal. It has high lifter bores with the bosses for the spider but they are not tapped. Cam is flat tappet. So my next question is, were there 350 Camaros in 1986? Were the engines in the 1987 Camaros using perimeter fastened valve covers? The fuel rails and manifold numbers are for 85 - 87 F bodies.