So whats the go with changing the knock sensor? Is there a different sensor for the 305 and 350. Im not actually putting in a engine from another car im buying a gm block and building a long motor then putting my 86 TPI on it, I have got a ECM out of a 87 350 Vette I was just going to change the eprom into mine, I was told that will work.Im not sure if the Vette chip is any different but ill have to try it. Its pretty hard to get TPI engines in Australia so you just have to make do over here. Parts are hard to get also you guys are lucky over there.

 

Does any body know if the wiring harness for the 86 Tpi dissy is the same as the 87, I am going to have to run the small cap dissy if i go 350 coz the 305 dissy wont match. It has different plugs and i dont really know if its going to fit because i have only seen photos of the small cap.

 

well you can use the 305 ecm if you get a chip made. the 305 and 350 ecms are the same just diff. chips the knock sensor are different for the 305 and 350, if you use the 305 chip you need the 305 one. if you use the 350 chip you need the 350 one. If you get the custom chip made just ask the progromer witch is the best for your setup.

 

So much mis-information in this thread.
MAF is 85-89
SD is 90-92 (for thirdgens)
305 and 350 ECM's are the same for the same years, only difference is the memcal (thirdgens)
19lbs are 305 injectors, 22lbs are 350 injectors
Small cap distributor can be swapped using a custom distributor adapter harness, you can buy it for about $40 or build one yourself.

If you get a roller long block with stock heads (from a thirdgen), you will need to re-drill the 4 center bolt holes in your TPI base to match the newer bolt angle.

 

The knock sensors are different 305 to 350.

You DO NOT need to match the PROM with the K.S. I ran my car w/ a 350 K.S. w/ a 305 PROM and it ran fine.