1.4T Cruze/Sonic Tuning Thread - Where to begin
Instead of clogging up the other thread, i figured we should start our own thread for others to find info easier.
- Attached is my stock tune and my current modified tune.
- You can do a compare against my stock tune to see what i have changed.
- Here is a rundown on the things that have made what i feel is a giant impact on performance.
Background: I had a aftermarket tuning solution in the car the last 6 months and while it def made a difference i didnt think it was as refined as it could have been. Wicked lean till 3500 rpm, surging under WOT which i found to be the result of a 10.3:1 AFR once above 4500 and 5-6 degrees of advance, with slight KR. Also i didnt like how fast the throttle ramped in, it was not linear at all! My car has an Injen CAI as the only other mod.
Starting with factory stock tune...
So here is where i started. I raised the TM functions (engine peak torque and brake torque) well above what i would see on the scanner for output torque.
Next was getting the AFR in line. i tweaked the pedal % for PE to be enabled to come in sooner. @ WOT I commanded about 12.2 coming in down low vs the 15.7-16.0 from 2500 thru 3500 and played with the maf scale in the proper hz range to get that to be where i needed it.
Next i moved to top end WOT and commanded a 11.7 AFR and then dialed in the maf hz range again to get this close. At this point NIGHT AND DAY performance increase with no other changes.
The car drove WAYYYYYYYY better than it ever had, the power delivery was linear and responsive. Best of all NO MORE WOT SURGING! and i didnt even have to re-gap my plugs from or to factory specs as others indicate being required to fix certain issues.
Next thing i attacked was the timing tables, i basically went against the grain here and got rid of other factors that alter the advance at WOT with the exception of the KR. I did get rid of timing adjustments for the variable cam spark too @ wot only. Next unorthodox thing i did was try ti get rid of/limit burst knock intervention. Now with all that done i start feeding 10 degrees into it then ramping up to 12. Its taking this timing too in 90 degree heat on just pump 93 and at stock boost level which appears to be about 15.5 psi. I see 1-2 degree spikes of KR here and there and i left it at that for now.
The top end pull is NOW how i feel it should be! it doesnt plain off at 4500 anymore and feel vauge thru 6k like it used to.
I havent dabbled with the boost much yet as im still trying to grasp the theory of the control methods, all i did thus far was raise the max boost levels and up the duty cycle about 5% and that brought the boost to 16.7 psi, so i gained about 1 psi doing that. Ran out of time to go further. I also left the dynamic airflow setting where they were for now too.
To sum it all up, even in 90 degree heat, the car is a riot to drive now! i can feed power in with my foot instead of it all showing up instantly and feeling that flooring the pedal actually makes a difference lol. And the car i feel is FASTER on 'close to" stock boost than it ever was with the other solution on its hottest setting which i logged to be about 21 psi. I compare the 3rd gear pull the car has to that of an LS1 f-body, obviously not that fast but thats where it does its dirty work now, feeling wise.
I should have some time this week to get my car on the dyno see where im at, its reporting a steady 165-173 ft/lbs across the whole power band thru the scanner now.
Its also worth noting too, that injen intake with the tube near the maf yet has NOT skewed my maf readings at or near idle, nor part throttle. havent changed from stock and they are -1.6 @ idle and -2.3 during cruise and 0 @ wot. They were approaching -15 at idle and -7.6 during cruise and WOT with the other solution.
