scott4.6

I have a bama tune in my car right now. I was playing with the tuner today and i have a option for a stock maf and also for a 90 mm lighting. So if i get a lighting 90 mm and choose that option ,, is that all i need to do to run the 90 mm? And if so is their any power to gain? Thanks

cliffyk

"And if so is their any power to gain?"

With your modifications the answer is easy--no, not a bit...

The stock MAF is a solid performer to 1100 kg/h (it pegs at 1220), which is 2425 lb/h. Running n/a at a 12.5:1 AFR there would be 194 lb/h of fuel mixed with that 2425 pounds of air--194 lb/h of fuel is good for 388 fwHP, 330 rwHP or so.

So you are good to go for a while, in fact the stock 80 mm MAF is better because you will be using a wider band of its total range (there is nothing to be gained, and something to be lost, by replacing a "non-pegged" MAF with a larger unit).

Guessing you are around 250 rwHP (295 fwHP) you maximum air need is in the neighborhood of 1850 lb/h.

Here are the MAF curves for the stock 80 mm MAF, the 80 mm '97 Cobra MAF (same as the '03 80 mm) and the 90 mm Lightning unit.



If you follow the Y-scale across at approximately 1850 lb/h you will see that with the 90 mm the MAF's output would be 3.9V or so. With the stock MAF the output at 1850 lb/h is 4.5V.

This means that with the stock MAF the usable voltage range is 0.2V to 4.5V, a 22.5:1 range; with the Lightening MAF it is only a 19.5:1 range. The wider the useful range the more accurately the PCM can calculate timing and fueling.

That's why different engine configurations use different MAFs, it would be a lot less costly for Ford if they could just use one MAF for every engine...

scott4.6

Thanks.

brent22

D**n cliffyK throwing some knowledge down!

scott4.6

Yes he did!! Thanks again