Re: Any feel like having a tuning discussion?
Another update. I just added about 15 gallons of gas. The MPG was 14.7. My driving is 100% city with trips less than 5 miles and hilly roads.
Previous MPG data:
1) With the modified aftermarket air box, ported throttle body, exhaust and a couple other little things I was getting a solid 13.5 MPG.
2) I faked the Inlet Air Temperature sensor (IAT) out with a resistor and added resistance in series with the Engine Coolant Temperature sensor (ECT) to get more timing. With the resistors, I would get between 14 (mostly) to 14.5 MPG.
The resistors were removed for the latest test since I had direct program control and I didn't need to "trick" the PCM.
During this 15 gal test run:
1) I modified the shift trajectory several times part way through. So the full effect of this is not known.
2) I made many wide open throttle (WOT) runs to check on timing, knock retard, and tranny shifting. The WOT runs hurt the MPG.
3) It's been colder so I idle more in the mornings before I pull out which hurts MPG.
The results are encouraging but this is just one data point.
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