pcmhacking.net

hello people, is there anychance someone can create a basic tuning of pcm ? im trying to do the simple thing of changing injector size but i dont understand it, loooks straight forward in the 11p basics with the MAP stuff but of course its not in the enchanced forum. i know there is injector offsets etc but idn what it means. i think ive downlaoded the faqs about 30 times am i missing a link somewhere ? its a vs turbo v6. is it seriously worth converting to a vr ecu and loom ? is the tuning more understandable? any guidence. please and thankyou

If anything, the MAF based pcm is easier. You need to change the injector rate , dead time, voltage offsets etc to suit your injectors in the injectors section. The pcm calculates how much fuel to inject based off the MAF frequency and the injector size to arrive at the desired injector pulse width.

In theory, on a stock car, if you change the injectors and put in the correct data the engine will run fine and the tune should be really close.

Also, you will need to do a little math to work out the cranking tables for starting the engine. When cranking the PCM just opens the injectors a set pulse width (during cranking) from tables.

As a rough guide, if you were to double the size of the injectors than you would need to half the injector PW values in the cranking tables.