tpi intake question.
iroczman
08-04-2006, 05:35 PM
well i got a 86 tpi intake and i want to put it on my '73 350 with stock heads and i was wondering what all i have to do to get it and running in my 89 iroc. 89 already has 305 tpi. i know that the intake should bolt up and the one sensor in the front will go and i will need a plug for the ninth injector but other than that what is there?
Blue Bowtie
08-09-2006, 09:48 AM
You'll need to pull the RH block drain plug and install the knock sensor there. Of course, you'll need to use a 350-specific knock sensor, since the 305 sensor is a lot more sensitive and will detect false knock. You can leave the cold start injector in place and simply not connect the cold start control and wire harness to it, or you can plug it. You'll need a different PROM. You can use the 19 pound injectors from the 305, but then you would need a custom PROM and may suffer starvation at higher load/RPM. 22 pound/hour is stock for a 350 TPI, and 24PPH injectors will work acceptably, but a custom PROM is still adviseable with them. All the rest of the sensors and controls are identical between the 305 and 350 TPIs. Depending upon the heads you install ('993s?) you may suffer a lot of lost compression and really poor flow. You might consider using the 305 heads ('187s?) and elongating the center two holes in either side of the intake base to accept the 72° bolt angle of the heads. The TPI heads are going to flow a lot better than stock smog-dog castings from the '70s, and with the 58cc chamber should give compression a good boost to close to 10:1. With a working EGR and ESC, that should be manageable on pump gas.
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