A friend of mine is converting his '87 IROC back to fuel injection from a carb. The long term goal is to convert it over to speed density and use an aftermarket intake like a stealth ram, but right now the priority is to get it running.

The car has a 350 L98 block with aftermarket heads and a mild cam, long tubes, etc. We were able to essentially get a donor engine, but it's a 305. The donor was originally out of an '87 itself, so we can see no problems with wiring harnesses, etc.

I am going to tune the computer for this thing, and I have decided to try and use the 6e definition file instead of the 32b. In this manner I can eliminate the cold start injector, etc. I have started with an APYP BIN and have made enough changes that I believe from a computer standpoint, the car will start. Since the ultimate goal is just to get the car running and driveable, I've turned the VATS off, set a rev limiter, adjusted fan temps, set the injector constant for 19# instead of 22# injectors, idle speed, etc. From a tuning standpoint, I don't really anticipate any problems there. My concern comes from some of the other physical things.

I have been told that the ESC, and knock sensors might be different for a 350 vs a 305 but nobody can tell me what is different exactly. The current block has been running a carb so it doesn't have any knock sensors, etc. It's easy to transfer all of this stuff from the 305, but we of course want to make sure it will work.

Is the 305 knock sensor completely different, does it need to be replaced or can it be made to work?

What about the ESC? I'll be honest I really don't know what this is about, my primary tuning experience is with early LT1's. Is this circuitry in the memcal? Will we need an actual 350 memcal? If so is one particular memcal more desireable than another?

The physical part of this swap should be very straightforward but we want to do our research first. We'd like to do it right the first time.

Thanks for all your input.

 

Well you have nothing to worry about, I went through these same headaches when using a 305 '165 ecm on a 350. Guess what everything is exacltly the same except for the injectors and timing, but since you are going to tune yourself neither will be a problem.