Today I tested the difference between SD and MAF mode both in open loop (Dyno inside)
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Today I tested the difference between SD and MAF mode both in open loop (Dyno inside)
For the sake of avoiding OCD i decided to go back to MAF operation for sometime to see how i liked it and if there was any difference. To my surprise the number between the MAF and SD were within .5 HP of each other. Here is the dyno graph that shows the proof
The car was dialed in using SD mode first and then some WOT power runs were made. THe maf was then hooked up and dialed in (fule only no timing changes) and I made some WOT pull with the maf. The graph appears to be off by one HP but that is because the decimal placed were truncated. These numbers were aquired on a Mustang Dyno using the Dyno Jet simulation. Run 1 denotes SD operation and Run 2 is the MAF. Enjoy
The car was dialed in using SD mode first and then some WOT power runs were made. THe maf was then hooked up and dialed in (fule only no timing changes) and I made some WOT pull with the maf. The graph appears to be off by one HP but that is because the decimal placed were truncated. These numbers were aquired on a Mustang Dyno using the Dyno Jet simulation. Run 1 denotes SD operation and Run 2 is the MAF. Enjoy
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MAF operation feel smoother/softer i assume this is because the maf damps a lot of the pulses compared to the map senosr. I will keep eveyone updated when i drive it more
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#8
Originally Posted by HumpinSS
Somewhere about 20* if I have the specs right but since the specs arent published I can only guess
Part throttle (non-PE) driving has to be better in SD, right???
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I will let you know it a week or so my Desired airflow and throttle cracker tables need to tweaked a little they were a little off in SD mode and still off in maf mode. I was being lazy. Other than that PT driveablitly feels about the same. The load dyno helped keep the driving conditions the same for both setups so they feel REALLY similar. after a week when the car settles in and I get a better feel for it i will report back
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Thank you for the good info... Like you said, I think the MAF softens part throttle up a bit if you tune it directly from dynamic airflow. Instead, I leaned the maf out just a bit with some help from MAF AFR histogram and part throttle livened up again by not over fueling transients. I find that once you dial in the MAF, some of the minor bucking and surging goes away and it handles changes in weather a little better too.
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Nice post glad someone took the time to post up and actully SHOW that there isnt a power differance between the 2.
I think he still had the maf in place when he tuned it SD just had it turned off. So the restiction part of the maf dosent come into play but that would be another good test to show the gains with out a maf in place to see if it is a restriction.
Originally Posted by Billiumss
Anyways, good post, MAFs aren't THAT restrictive as some people might think they are.