MAF Calibration

TT331FB · 09-07-2005, 08:15 AM

I have researched this topic and found tow opinions. Before I elaborate, here is my cal sheet for a 3" protube, 88-95 Mustang, 42# SC

Actual flow Calc Flow %ERR
Kg/Hr Volts Kg/Hr
1284.13 4.2777 1423.28 10.84
908.72 3.7287 1016.30 11.84
527.76 2.9726 588.04 11.42
322.32 2.3663 349.30 8.37
183.52 1.8219 204.95 11.67
108.75 1.3893 124.86 14.81
64.73 1.0050 72.00 11.23
37.44 .6449 37.03 -1.09
20.47 .3351 19.12 -6.58

One source I found said that the actual flow should be used while another said to use the calculated flow. Notice the % Error column. This one is interesting to me. My theory is that the calculated flow is the fudge factor they use for SC applications which I heard was about 10% rich.

I used the Calc flow and found the upper end of the curve rich about 15%.

Input on which air flow worked for you would be great.

Dale McPeters · 09-07-2005, 09:29 AM

'88-'95 = Actual Flow
'96-'04 = Calculated Flow

TT331FB · 09-08-2005, 08:59 PM

Dale,
I had seconds thoughts on this subject. The only folks interested in a curve are the tuners users. Why would anyone want to enter anything other than the actual flow?

Dale McPeters · 09-09-2005, 07:06 AM

Quote:

Originally Posted by TT331FB

Dale,
I had seconds thoughts on this subject. The only folks interested in a curve are the tuners users. Why would anyone want to enter anything other than the actual flow?

Well that is the million dollar question......

I converted about 15-20 MAF transfer functions in a row back when Pro-M was still Pro-M for the '96-'04 EEC-V cars, for people that were using the Pro-M meters. By using the actual flow like we would normally do on an '88-'95 EEC-IV car I could never get the transfer function to even come close to what Pro-M was sending me, I think that Bob (boss96) was one of the one's that I tinkered with in my testing. The only way that I could even come close to the converted 30pt. sheets that they were sending me was to do it as I posted above.

I had used the actual flow for conversion for years and this really had me stumped.............

I even tried it on the '03 Mach 1 that I had with the same results.
Bob made a post on this a while back but can not remember what his opinion was....

I still use the above method for the ones that I convert from 9-37pt to 30pt. I have only converted 1 meter that has came from professional mass air systems so the verdict is still out on what method will work the best.....

I have notes on my findings somewhere.....

.....but I have been so busy on my own little projects and trying to work at my real job that I just have not had the time to mess with Ford EEC tuning to much....except on my own cars of course..

When we get my old 347 installed in Lee H.'s car and I get thru welding on the rear of the '93gt I will see if I can dig up some of that info. I also have to send Lee (QWKSNAKE) some things to post for downloading.

Just not enough hours in a day, week, or month anymore.....but I will get to it eventually....

boss96 · 09-09-2005, 10:32 AM

I had to use calculated flow to get mine to work, like Dale said, when I did it the other way my meter calculated out to 8000kg/hr on the top end!
Doing it the other way made it come out close to what ProM had sent me, which was 3000kg/hr.
Even so, after tuning with my combo I ended up reducing the max flow to around 2200 but that is combo specific.
Bob

TT331FB · 09-10-2005, 09:20 AM

Regarding my Pro Mass Air meter, the calculated numbers were lean on the low end and rich on the high end. The meter is a good install, with 18" of straight run before the MAF.

It would be good to understand the calculation they use but they may have lost the ability to understand it themselves.

09-07-2005, 08:15 AM	#1
TT331FB Member Join Date: Aug 2005 Posts: 53	MAF Calibration I have researched this topic and found tow opinions. Before I elaborate, here is my cal sheet for a 3" protube, 88-95 Mustang, 42# SC Actual flow Calc Flow %ERR Kg/Hr Volts Kg/Hr 1284.13 4.2777 1423.28 10.84 908.72 3.7287 1016.30 11.84 527.76 2.9726 588.04 11.42 322.32 2.3663 349.30 8.37 183.52 1.8219 204.95 11.67 108.75 1.3893 124.86 14.81 64.73 1.0050 72.00 11.23 37.44 .6449 37.03 -1.09 20.47 .3351 19.12 -6.58 One source I found said that the actual flow should be used while another said to use the calculated flow. Notice the % Error column. This one is interesting to me. My theory is that the calculated flow is the fudge factor they use for SC applications which I heard was about 10% rich. I used the Calc flow and found the upper end of the curve rich about 15%. Input on which air flow worked for you would be great. __________________ TT331FB - T3/.6/.63 turbos, Spearco intercooler, 302/331 Mexican Block,AFR 185 heads, 80mm MAF, 75mm TB, 50# injectors, Tweecer, Track Heat intake, Comp cams roller blower grind, MSD BTM, DIY-WB, Yokogawa video display,T-56 tranny, 9" 3.5:1 Traclock, 4x disk brakes, TCP most everything, shelby roll bar. First fire up 2/14/2004.

09-07-2005, 09:29 AM	#2
Dale McPeters 5.0 Block/Walnut Cracker Join Date: May 2005 Location: Working.... Posts: 2,409	Re: MAF Calibration '88-'95 = Actual Flow '96-'04 = Calculated Flow

09-08-2005, 08:59 PM	#3
TT331FB Member Join Date: Aug 2005 Posts: 53	Re: MAF Calibration Dale, I had seconds thoughts on this subject. The only folks interested in a curve are the tuners users. Why would anyone want to enter anything other than the actual flow? __________________ TT331FB - T3/.6/.63 turbos, Spearco intercooler, 302/331 Mexican Block,AFR 185 heads, 80mm MAF, 75mm TB, 50# injectors, Tweecer, Track Heat intake, Comp cams roller blower grind, MSD BTM, DIY-WB, Yokogawa video display,T-56 tranny, 9" 3.5:1 Traclock, 4x disk brakes, TCP most everything, shelby roll bar. First fire up 2/14/2004.

09-09-2005, 10:32 AM	#5
boss96 Member Join Date: May 2005 Posts: 47	Re: MAF Calibration I had to use calculated flow to get mine to work, like Dale said, when I did it the other way my meter calculated out to 8000kg/hr on the top end! Doing it the other way made it come out close to what ProM had sent me, which was 3000kg/hr. Even so, after tuning with my combo I ended up reducing the max flow to around 2200 but that is combo specific. Bob __________________ 1996 GT, forged parts, vortech, ZXA3 processor, etc.

09-10-2005, 09:20 AM	#6
TT331FB Member Join Date: Aug 2005 Posts: 53	Re: MAF Calibration Regarding my Pro Mass Air meter, the calculated numbers were lean on the low end and rich on the high end. The meter is a good install, with 18" of straight run before the MAF. It would be good to understand the calculation they use but they may have lost the ability to understand it themselves. __________________ TT331FB - T3/.6/.63 turbos, Spearco intercooler, 302/331 Mexican Block,AFR 185 heads, 80mm MAF, 75mm TB, 50# injectors, Tweecer, Track Heat intake, Comp cams roller blower grind, MSD BTM, DIY-WB, Yokogawa video display,T-56 tranny, 9" 3.5:1 Traclock, 4x disk brakes, TCP most everything, shelby roll bar. First fire up 2/14/2004.