It is kind of a long term project I've always thought about, but I was wondering if anyone else had the same kind of idea??

Today it's easier than ever to build a dedicated system with programmable microccontrollers. And then you could program it on the fly, unlike the stupid GM ECMs that only have PROMs

The main reason to do this would be cost - After the TBI unit, you'de be talking pennies.

The hardest part would be knowing what algorithm/lookup tables to program the FI unit with.

Has anybody ever attempted? I plan on starting small and attempting to fuel inject a lawnmower - just to experiment a bit.

What are your guys' thoughts???

 

If you aren't familiar with 'megasquirt', it would be worth doing a google search for.

 

Uhh, just so you know, the stupid GM ECM's can now be programmed on-the-fly. And also, just so you know, the most crucial part of tuning is taking notes so to know what change did what, which is something most guys forget to do when tuning on-the-fly. And as a last so you know, the original programming hours involved in getting a GM ECM PROM right so that it could fit the needs of every car they sell with that programming is probably somewhere in the several thousands. Well, have fun building something from scratch or save yourself some time and go with the recommended megasquirt. Or just do the easiest thing and burn a PROM for the stupid GM ECM.

 

Well, since you seem like an expert, how exactly DO you program a PROM on the fly - withOUT rewiring the entire ECM???

:hail: :hail: :hail:

 

Hang on a second, no need to bow or call me an expert. I am deserving of neither. All you would have to do is check out the DIY-PROM board and you would know. Or just go to www.tunercat.com And the original programming was done on the fly by gm code writers. There is a way to do it but it involves doing some crazy deal with ram and other things I have no knowledge of. As a matter of fact, the Australians have been doing it for years with some kit called Kalmaker or something. They use it for the Aussie 165 ecm known as the 808.

 

You use an emulator.

As mentioned you can get the software for on the fly editing from www.tunercat.com, and then using a Romulator from Xtronics, in fact do on the fly tuning.

GM with the millions they spent on ecm design is going to be hard to match. Lots of the GMs use a memcal and that holds all the programming on it and is seperate from the ecm. The early ones had on board ROM that were hard to work with.