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turbo lcc
March 22nd, 2007, 12:58 AM
Is there a procedure/tutorial for dailing in the MAF?
SSpdDmon
March 22nd, 2007, 01:48 AM
It's just like the VE. Make a table like the one in the tuning software - 1 column with MAF Hz as the rows (1,500-12,000 in steps of 125). Then, use the BENs to adjust. As you get closer to being dialed in, don't apply the full BEN correction - only apply 25~50%. It will help to avoid overshooting the target.

The key is to get good data. So, use your filters to eliminate unsteady throttle, DFCO, and low airflow scenarios (ie TP%<5%). Once you know what good data looks like, get lots of it. Rinse and repeat. :)
turbo lcc
March 22nd, 2007, 02:00 AM
Do any tables/function in the ECM need to be disabled such as DFCO or LTFT/STFT? Or can the MAF be dialed in as the car is drivin daily?
SSpdDmon
March 22nd, 2007, 04:11 AM
If you're using a WBO2, I'd turn off DFCO and the LTFT's/STFT's. You're basically doing the same thing as the VE. So, you're going to want to eliminate the outside factors and have your commanded fueling set appropriately.
dc_justin
March 22nd, 2007, 07:08 AM
Another way (to ensure that VE and MAF jive) is after your VE table is dialed in but before you re-enable your MAF, log DYNAIR and map it against your MAF hz as SSpdDmon described. Then go out and try and fill out as many cells as your can.

If you prefer the BEN factor method, make sure you disable airflow calculations by lowering B0120 to some number below your idle rpm.

Edit: They DYNAIR method will be much quicker since you've already completed the BEN process with the VE table, and this is just a method of mapping the VE to the MAF calibration... sort of.
SSpdDmon
March 22nd, 2007, 07:57 AM
Another way (to ensure that VE and MAF jive) is after your VE table is dialed in but before you re-enable your MAF, log DYNAIR and map it against your MAF hz as SSpdDmon described. Then go out and try and fill out as many cells as your can.

If you prefer the BEN factor method, make sure you disable airflow calculations by lowering B0120 to some number below your idle rpm.

Edit: They DYNAIR method will be much quicker since you've already completed the BEN process with the VE table, and this is just a method of mapping the VE to the MAF calibration... sort of.
Good point. However, I noticed this tends to overshoot some. But, at least you'll be working from rich to lean instead of lean to rich.