Hi all,

I am swapping a 1985 TPI engine into my 1988 Iroc since the original engine has developed a rod knock. I am planning on removing the TPI setup and ecm from the 1985 block and installing the 1988 TPI setup and ecm onto the 1985 engine block. Does that work? Can the 1988 TPI and ecm work with the 1985 305 engine? A friend was telling me that only the 1985 TPI ecm would work with the 1985 engine, and that the 1988 ecm wouldn't. However, I don't see why it wouldn't work. Thanks.

 

The computer does not know or care what year engine it is controlling ,so long as you have the correct 305 tune in the computer

As there is no difference why would you go to the trouble of swapping the TPI intakes ?
Drop the 85 engine in and use the 88 wiring and computer

 

OK thank you for your response. So my final setup will be a 1985 305 engine block with a 1988 TPI setup and ecm paired with it. Sorry for my questioning, but what is the 305 tune? Thanks.

 

Like I said why change the TPI intakes if they are already on the engines?

The F-Body 86 - 89 305 and 350 TPI engines use the same ECM (computer ) and wiring as does the Vette.

The tune on the memcal (chip ) fitted inside the ECM determines what combo it is setup for.
Even though there is no difference in the TPI intake , 305 vs 350 ; you can't use a 305 memcal ( tune ) to run a 350 or vise versa .

 

Ok so I am good then. As for why I am changing the TPi intakes, when I remove the 1985 305 engine, I will be removing the heads on it and installing new ones. The 1988 TPI plenum and runners are in better shape than the 1985 plenum and runners. Since the 1985 TPI plenum and runners will already be off anyway, I will just replace it with the 1988 TPI setup. Thanks for all your help.

 

But as they are the same item you should stop calling them a "85" and a "88" ; only causes confusion
All you are doing is replacing one early TPI intake with another one in better condition