I have a 1986 Z28 Tpi 305 and want to put a 1988 350 Tpi in. Will the Harness work for the 350. I think the computers are the same and i would have to use the 350 chip. Both are automatics. What else would i have to have?
five7kid
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Apr 26, 2026
The harness is the same. In fact, all hardware is the same except for injectors and knock sensor.
And, in '87 they went to a different intake mount bolt angle for the center two bolts on each side. You can either buy an aftermarket base for '87-up pattern, or trade your '86-earlier base for someone's '87-later base. If you're getting the all of the '88 TPI hardware with the engine, never mind...
350 knock sensor & module, and injectors, are also different from their 305 counterparts.
Other than that (and the 350 chip you mentioned), you shouldn't have any issues.
And, in '87 they went to a different intake mount bolt angle for the center two bolts on each side. You can either buy an aftermarket base for '87-up pattern, or trade your '86-earlier base for someone's '87-later base. If you're getting the all of the '88 TPI hardware with the engine, never mind...
350 knock sensor & module, and injectors, are also different from their 305 counterparts.
Other than that (and the 350 chip you mentioned), you shouldn't have any issues.