MAF Scaling Methods

As mentioned in my earlier post, since I have changed my stock intake to an APS CAI 70mm, I need to re-scale my MAF.

After doing alot of research on the Net, I found 2 methods to scale my MAF, found on nasioc.com and on romraider.com. Both methods uses spreadsheets to run statistical calculations/analysis to determine the final MAF calibrations.

1. williaty's method: http://forums.nasioc.com/forums/showthread.php?t=1427448
2. mickeyd2005 method: http://www.romraider.com/forum/topic1871.html

There's actually another method here but it's not as detailed, though it's for exactly the same intake as mine. It still makes a nice read though: http://www.iwsti.com/forums/cobb-street-tuner/54421-aps-70mm-cai-intake-calibration.html


williaty's method requires abit more time once you have logged the necessary parameters since you perform each step manually (perhaps it can be automated using macros).

mickeyd2005's method is faster since he has already built a spreadsheet to automate all the tasks but be warned, you need to study the data points and determine which one is valid. Also, do remember how your driving style was when you were logging as it will determine which MAFv ranges are ok to use.

In my opinion, both methods works fine but one thing's for sure, don't expect to get quick results, you need alot of patience to log and study/understand the data before making changes or else you are only making matters worse.

Some tips:
1. Log good data, not just ANY data. What I mean is for both methods to work fine, you need to be logging MAFv which is in constant state, i.e. when you are driving on a highway with constant throttle and steady driving. If are logging in conditions where you are in constant stop/start conditions, your data is probably not that great.

2. Go for more data rather than more iterations. Of coz, log good data.

3. Try to make small number of changes as you progress into more iterations. Reason being you are probably in fine tuning mode as the number of iterations increases and thus big changes will most likely have a big impact, wasting your previous iteration efforts.

4. Study each data point and value you are going to change, if possible look back to older data/graphs to study the impact of previous changes/values.

5. Be patient. :-)