I have the oddest combo possible.....

[lt1stang]

Ok... i have a very odd combo. I have a LT1 that has the efi connection 24x conversion to use the LS style PCM and eliminates the Optispark. This engine is a turbocharged engine (88mm). So far things sound fairly normal... but here comes the twist... THe engine is in a 1995 Ford mustang and I want it to be truly flex fuel compatible. I started this project a few years ago. i recently changed jobs ( I am now a automotive service technology instructor at my local high school career technical center) This stagnant project has now become a very active project that my students are excited to complete. Since I have no tune to start out with and the engine is turbocharged ( I intend to use a 2 bar map sensor) I am interested in a COS that will allow the use of a 2 bar map. Can I use a COS for the 12579405 tun and copy the flex fuel tables from the 12216125 flex fuel tun? Any suggestions welcome..... P.S. I have a factory GM Flex fuel sensor from a 5.3 Z code truck.

[ScarabEpic22]

What OS are you currently using? The best bet is to use the factory flex fuel OS and its associated COS (if it exists), if not you might have to hardwire the COS to default to a particular octane scaler value. I.e. flip a switch, the PCM defaults to the low octane table to use with E85, flip it back and run on the high/low. Just an example, I dont know if you run more/less timing on E85.

Might be odd, but sounds like a sweet project to me!

[lt1stang]

In searching about my situation it appears there is not an COS that works with the 12216125 tun . I do not have in OS in my PCM as it was a unflashed reman computer from Standard Ignition. I originally intended on using the 12216125 tun but after reading this post. http://forum.efilive.com/showthread....-Fuel-Question It became apparent I was going to have to resort to a different approach.