My buddy and I are getting into chip burning and I have a spare 305 PROM for a 730 ECM that he wants to use in his 350. I don't want to rip anyone off, especially my friend, so I'm trying to see if this chip is compatible with a 350 (assuming the fuel tables are changed accordingly). Thanks!

 

there are two aspects to consider.

one is the PROM, the thing that actually holds the code. It's the thing we program. Once you electrically remove it from the picture (with a moates adapter, or any other way) it doesn't matter what used to be on the original PROM. so from that aspect, it doesn't matter one bit that the memcal was originally a 305 memcal - you're replacing the code anyways.

on the other hand, the bottom half of the memcal has a resistor network on it that handles limp home duties. And on SD setups, I believe it also has the knock sensor filter, and is thus tuned to the particular engines knock characteristics (305 vs. 350).

Personally, I'd try to keep the memcal in line with what the engine is. so far, I don't think anyone knows how to tweak the resistor network (resnet) to make limp home mode work better for modified engines, so we just deal with that, but certainly you want the proper knock sensor filter for your (or your buddies combo) - unless he isn't running a knock sensor anyways.
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thread 255874 may also be useful to you. I don't know how to link to other threads anymore on this new software, but if you search for 255874 it should come up.

 

this link might work

https://www.thirdgen.org/forums/diy-...-mem-cals.html

 

Thanks, I figured the limp mode wasn't tuned for the specific engine- oh well. Thanks!!