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Actually fuel pressure is VERY important at WOT, since the ECU cannot adjust fuel trims for extra air in the cylinders, when boost is applied to the mix. At WOT, the ecu is in open loop, where it resorts to pre programmed fuel maps to inject fuel, and does not adjust fuel off of the o2 sensor. Fuel pressure alone is what will give you more or less fuel at WOT. If you are running 5 psi, then shoot for fuel pressure to be around 85 psi. You will need to monitor your EGT's and make sure it goes to no more than 1550 degrees(before the turbo exaust temps).
LTFT is the ecu's fuel adjustment "headroom". It goes from +25% to -25%. When LTFT is at -25%, this means that the ecu is leaning out the fuel mix 25% over the stock programmed fuel map ( 0 %). This happens over longer duration, which is why its called LTFT.
STFT is the ecu's instant fuel adjustment percentage. This will tell you exactly what the ecu is doing with your fuel at any given point in time. Reading a datalogger while driving, lets say your STFT is at -15% while you are lightly boosting, not at WOT. This means that the ecu is adjusting and leaning out your fuel by 15% from the stock programmed fuel trim ( 0 % ). STFT will constantly be changing with different engine conditions, but should stay from +5 to - 5 % for best ecu adjustment capability. Its this reason that having your STFT maxxed out to -25% isnt good, becasue now the ecu is leaning out your fuel as much as it can, and you will run rich, and throw a CEL code. Then if your motor goes from leaning out that much, to a instant demand of needing more fuel than the stock fuel map, the ecu may not be able to go into the + numbers fast enough, and then you can run lean. Positive #'s means the ecu is adding fuel over the stock fuel map. Hope this makes sense. YOu basically want your STFT to stay between +5 and -5 for the best, but realistically, anywhere from -15 to +15 would be ok, but that would be the limit for tuning IMO.
You did put the ring around the 2.72" disk right?? The largest disk the SFMU comes with does NOT have a ring around it, but all smaller disks have a ring that goes with it, so be sure you have the ring around the disk, i assume you do, just checking The proper ring will have a 1/4" gap from the ring to the outer edge of the 2.72" disk.  13.5 @108 MPH-2.2 60ft(stupid FWD!) S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential fuel injection) My webpage: http://eclipsed4evr.home.comcast.net -1998 Mitsubishi Eclipse RS-T- "Toy" -1992 Plymouth Laser Turbo AWD(SOLD) -2000 Honda CR-V(daily)
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