Apexi S-AFC II + mods
#32
Although this may have been pointed out already.. Its important to note that most of you guys have posted settings with a negative correction at low RPM's.. Some air intakes cause the MAF sensor to read differently than the stock airbox.. therefore essentially leaning out your mixture.. I have found that ALL of those negative corrections posted under load, at boost, between 3000-4500rpm are generally TOO Lean with an aftermarket filter. With a stock Airbox, or an air filter that doesn't cause the MAF to Mis-Read, you can lean it out at those ranges, but because the MAF is already misreading lean, the car may end up superlean when you really need the "breathing room" of a slightly richer setting.
Take it from experience..
and I have to agree with everyone else who's had input, an EGT sensor and a Wideband O2 sensor is essential to tuning.. detonation and extremely high EGT's are both contributors to engine damage.. Timing (the timing adjustments caused by fouling with the MAF reading and its associated load points) will have a direct effect on EGT's along with shifting/killing the gains and that should be taken into account.
Since you are only adjusting the MAF reading, and what the ECU thinks as a different load on the engine, it will indirectly alter the timing based on the same factors, its a balancing act because there's a "Sweet spot" at each rpm step where both the timing and mixture are at a level which will make good power.. Timing is retarded under high RPM because of the "Timing window" between the acceleration of the compression stroke, and top dead center.. Too early (or preignition due to too much heat, too much boost, etc) and you get detonation.. Too late at that given RPM, and you get unburnt gas in exhaust stroke, these escape on the exhaust stroke. Of course ignition timing and cam timing, lift and overlap are also related since their all timing events which may or may not be able to be controlled easily.
There are more technical terms, and details that contribute to this, but I'm trying to
Another good point is sustained exposure to those EGT high temps could melt things (like an aluminum head) and you may not get detonation for one reason or another and still get a catastrophic failure.
Its always safer to error on the conservative side
I may have had a brain fart when writing this so feel free to point out any technical errors I may have made.
Take it from experience..
and I have to agree with everyone else who's had input, an EGT sensor and a Wideband O2 sensor is essential to tuning.. detonation and extremely high EGT's are both contributors to engine damage.. Timing (the timing adjustments caused by fouling with the MAF reading and its associated load points) will have a direct effect on EGT's along with shifting/killing the gains and that should be taken into account.
Since you are only adjusting the MAF reading, and what the ECU thinks as a different load on the engine, it will indirectly alter the timing based on the same factors, its a balancing act because there's a "Sweet spot" at each rpm step where both the timing and mixture are at a level which will make good power.. Timing is retarded under high RPM because of the "Timing window" between the acceleration of the compression stroke, and top dead center.. Too early (or preignition due to too much heat, too much boost, etc) and you get detonation.. Too late at that given RPM, and you get unburnt gas in exhaust stroke, these escape on the exhaust stroke. Of course ignition timing and cam timing, lift and overlap are also related since their all timing events which may or may not be able to be controlled easily.
There are more technical terms, and details that contribute to this, but I'm trying to
Another good point is sustained exposure to those EGT high temps could melt things (like an aluminum head) and you may not get detonation for one reason or another and still get a catastrophic failure.
Its always safer to error on the conservative side
I may have had a brain fart when writing this so feel free to point out any technical errors I may have made.
#33
Masterevo,
FMIC working great... been getting constant intake temperatures all the way.. and from a country with 30+ degrees C all yr round.. that's good.. the install and mount was pretty straight forward.. you have to remove the front bumper and underside panels to install.. the only problem from this is if you are using hardpipe intake kits.. the greddy comes with piping and will only attached to the stock piping or the greddy hardpiping kit to the throttle body.. HKS doesnt fit.. Cost of the kit here is about $1900 or about US$980.
MalibuJack...
Yup... the aftermarket filters draw in more air then the stock box.. hence corrections have to be lower than with the box... that's why a Wideband and a Dyno is an essential to good tuning...
Conduit....
EGT sensor mounted on downpipe just after the bend towards the CAT area... this location was suggested by Koyama of Jun Auto..
FMIC working great... been getting constant intake temperatures all the way.. and from a country with 30+ degrees C all yr round.. that's good.. the install and mount was pretty straight forward.. you have to remove the front bumper and underside panels to install.. the only problem from this is if you are using hardpipe intake kits.. the greddy comes with piping and will only attached to the stock piping or the greddy hardpiping kit to the throttle body.. HKS doesnt fit.. Cost of the kit here is about $1900 or about US$980.
MalibuJack...
Yup... the aftermarket filters draw in more air then the stock box.. hence corrections have to be lower than with the box... that's why a Wideband and a Dyno is an essential to good tuning...
Conduit....
EGT sensor mounted on downpipe just after the bend towards the CAT area... this location was suggested by Koyama of Jun Auto..
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