Just finished modding my Daily Driver 2007 Grand Prix GT.
It was a Christmas gift to myself !
Went from 100% stock to:
Since it's a 2007 used a 2005 ECM by Overkill.
That worked well and improved the car's 0-60mph by .5 seconds and made it more fun the drive.
It took away the KR I had on 91 when I was 100% stock.
Then installed 3.0" pulley
and installed a Methanol Injection kit with a very large jet.
Made an intake tube, welded some bungs.
Obviously since the tune wasn't made for that pulley and a methanol kit which enrich a lot, it ran really bad with those 2 mods (misfire and knock)
I then went into HP tuners to edit the fueling table. I left the timing map alone. That completely fixed it, with only 1 tune, it is perfectly tuned (safe).
There is zero knock to be found.
Better yet, since it's very cold here, I run 15 psi of boost + with the 3.0" pulley and the logs show up to 49 lbs per min. Huge power. The car pulls very hard.
On dry pavement, I can roll into the throttle in 2nd gear and light the tires up all through the gear.
Really impressed with the power, the cold weather + 16 deg of timing + 15 psi of boost on a Gen V is a lot of fun.
My other 1997 GTP ran 12.9 @ 107 mph and only had 39 lbs/min of airflow. This car has 10 more lbs/min which means it makes nearly 90 HP more and with a larger pulley.
Just wanted to share.
