im tuning my car and i got it nice and steady at about 11.2 droping to 10.8 by red line in 2nd gear. but then in 3rd or 4th gears it is in the low 10's. this is at the same throttle percentages. correct me if im wrong, but shouldnt it run slightly leaner because of more load in a higher gear? then why is my car fatter in the higher gears than lower?

 

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Probably because your boost is droping. Bost is easy to stay high in lower gears asa their is massive acceleration and LOAD forces. The stock Wastegate is what, set to 8-12 Pounds, meaning if you have no boost control, you will only have 12PSI, tighten your wastegate actuator to like 18-19PSI. But doing this will make it impossible to run less then 18-19PSI, but you shouldn't run less anyways.

 

Not necesairly,as you increase load, you typically decrease timing which can actually cause a change in AF as recorded by the wideband. Makes sense if you think about it. As the timing is reduced to prevent detonation, the charge is ignited later in the cycle which allows more time for burning/unburnt fuel to make its way past the WB.

 

Phantom Knock yeah that's a killer

 

phantom knock... as in my ecu thinks knock but here isnt any so it pulls timing? i shouldnt be knocking with my setup.

 

I've seen the same using a wide band. Lower gears (2nd-3rd) see 11.3-11.7, shift to 4th and they drop to 10.8-10.9. As fas I can see with my EVO and from past experience with my DSM, the higher the gear, the more boost is held. In this car, 1st, 2nd boost drops off fairly quickly. Thrid gear holds boost where I set it a little longer, but 4th holds pretty good.

But I'm not sure why the a/f gets richer in higher gears when I also thought it would get leaner.

 

i really dont think its knowck, i feel nothing that would make me beleive the motor is pulling timing, the car is pulling too smooth and too strong for that. and besides i use only shell petrol and when i reset ecu, it drives the same.

 

I dyno'd last year in 3rd and 4th gear back to back. 4th gear was way richer.