WOT Tuning

[mrand]

Originally Posted by Starman

Guys, as I recall the LT-5 is programmed for a 12:1 fuel/air ratio with the secondary injectors on. It will be faster if you lean it out (ideal stochiometric ratio for gas is 14:1), but it is programmed rich to protect against detonation. Let's face it, the 90-92 cars have 2nd generation ECMs and only read every 25 RPM. With Speed Density control and batch fired injectors there is not much to work with here. You can detonate the hell out of the car without it responding enough to prevent it, just on a bad tank of gas.

The 93 up cars have the P8 ECM that read every RPM. I've often thought that there would be more driveability there but have not found anyone that has made the change.

I'm sorry to say that, regarding LT5 applications, there isn't much correct in this quoted post.

"Ideal stochiometric ratio" describes a chemically balanced mixture - it has nothing to do with best performance. Leaning out the AFR of a performance engine at WOT to anything approaching 14:1 is a recipe for disaster.
Has has been pointed out, the LT5 injectors are not batched fired.
The computer runs plenty fast to respond to rpm changes. The post makes it sound like the computer sits around and once every 25 rpms does something. That isn't correct. And while a bad tank of gas could cause a little detonation, there is a knock sensor which will prevent "detonating the hell out of the car." And really - do people get "bad" tanks of gas any more? Lastly, the computer used in 1993 was not noticeably different than the one used in previous years.

Marc