[naz]

darkpuppet,Mar 31 2004, 11:44 PM Wrote:I find it interesting that everyone views that 5V cutoff at the PCM as a hard ceiling, and that everything connecting to it runs the same.

The fact that the MAF can send a signal up to the full 12V sorta opens up other possibilities I think...which makes me wonder why this question wasn't asked before....

well.. isn't it sort of a hard ceiling though? maybe not a "stuff stops working after 5V" but for all intents and purposes it might as well

if the PCM tables only have values for up to 5V how are you going to control the engine properly when the MAF signal goes above 5V

you can build a circuit to apply a transfer function or use an interceptor thingy like those Apex-i SAFC but those still won't do load calculations for you, and therefore can't adjust the ignition timing properly. i don't completely understand the load calculation process but i do know that it takes more than just the MAF signal as an input.

and so now instead of just repopulating the PCM tables with different values, you need to use some device to rescale the MAF signal, and you still need to repopulate the PCM table with different values anyway, so you get the load calcs and other stuff right

i think that's why using a recalibrated MAF together with its appropriate flow bench test sheet is the 'prefered' way to go because you don't have to do 2 sets of calculations, only 1, and because you are using the PCM directly, you don't add possibility of failure by using another component..

IMHO bro, why don't you just pony up for the recalibrated cobra MAF, and go with the proven solution instead of being a pioneer and experiencing the crap that comes with that

if you can afford that bling bling headunit.. you can pony up $250usd for the MAF man...