Thread: How to change MAFs in a BIN?

can anyone tell me the k-value for a de maf and 259cc injectors (stock)?

is it 31206 (that's what i found searching google)?

31206 is what i have on a bunch of 91-93 stock ser usdm and jdm bins.

thanks man. what i found was the k-value in calums ve tune for the de maf maybe wrong (27878).

i calculate it to 24271 = (259cc / 333cc) x 31206

i am thinking of this correctly?

You are thinking correctly in terms of calculating a new K value if you changed injectors on a DE from 259cc to 333cc. But that does not mean that Calum has the "wrong" K value in his VE tune. I say this because it's a different engine and (I'm assuming) a different fuel map. Different engines (VE vs. DE or even one VE compared to another VE) need different amounts of fuel under different conditions (load and RPM) and the values in the fuel map influence the injector pulse width as well as the K value.

At some point, one shifts from theoretical calculations to tuning with empirical observations using a wide band. Calum has done that for his VE tune. That said, further customization of the tune using a wide band will be needed to optimize it for another car -- this could involve changing K to other values to provide more or less fuel across the fuel map. Then the individual cell values on the fuel map can be used to make more specific changes.

as well as working with your tp scales and injector latency...

does any particular direction that you move the k-value tell you whether its richer or leaner?

Increasing K increases the injector pulse duration (and fuel delivery) in an amount proportionate to the change in the K value.