Thread: Q45 MAF, good for 700 HP?

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2012-11-12 05:19:12

#31

ashtonsser Online/offline status of ashtonsser is unknown

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Your right, i was dividing it against the wrong number. My bad. So in essence your taking away 32% fuel. Its been a while since ive had to do calcs for an SAFC. lol

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2012-11-12 05:25:02

#32

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Last edited by ashtonsser on 2012-11-12 at 05-32-58.

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2012-11-12 12:14:10

#33

blo0d

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Originally Posted by Lynx

Originally Posted by ashtonsser
No different than changing from one maf to another.

well for me changing from one maf to another = one click. I suspect this is slightly different.

Does the vq curve stay the same? Multiply all values by the change in area? Wont your idle read lower, potentially hitting the low voltage trigger and going into maf unplugged mode?

you wouldnt be making changes of this nature without knowing that you need to change your voltage trigger to 0.07v (lowest voltage in VQ is 0.08v)

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2012-11-12 12:16:56

#34

blo0d

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Originally Posted by ashtonsser

Its not off, the same calculation is used when determining the difference in injector size and how much fuel you should be taking away for those that use an SAFCII or want to use math to calculate fuel changes in the VQ tables.

say your ecu is tuned for 370cc injectors and you put in 550cc injectors. Thats a difference of 180cc.

You would take 180/370 = .49/ converted to % by multiplying by 100 = 49%. The 550cc injectors is a 49% larger injector than the 370cc. In other words you would have to take out 49% fuel to get the same a/f ratio you had before. Same goes with calculating maf housing size.

this is the correct way to calculate percentage change....