My over-the-winter projects included installing a new fuel pump along with an M3 baffle, H&R Sport springs, new OEM rear trailing arm bushings (RTABs, without limiters), new front sway bar bushings and endlinks, and 200TW tires. For safety I also installed new OEM brake lines, and after all of this, had the car aligned at the BMW dealer (!).
My take-aways: The car feels awesome for what it is. I can't believe the difference actually-- Night and day would be an understatement. With tire pressures set at 34F / 40R there is almost zero understeer, and I can basically toss the car wherever I want on the track with smooth inputs, brakes and throttle. The car feels light and nimble, and didn't feel at all out of sorts or with any bad habits during weight transfer. In three 20 minute sessions I was passed by one (1) car, which was a Spec E46 racing car...! The 2.93 gear, which I thought was a bad thing, is actually great in this car, as I can basically stay in 3rd and 4th gear for most of the track, with 2nd only in the slowest of turns.
The only downside is that this thing desperately needs a limited slip diff. This negative factor is really magnified now; it was bad before, but with the increased cornering loads the traction control is basically coming on all over the track. I held off on the LSD thinking I'd replace with a shorter gear (the LSDs for 3.15 and lower are a different application), but there's really no reason to go away from the 2.93 for what I'm doing.
The LSD aside, the most surprising aspect now is the ability to smoothly carry momentum through turns and exit with more speed. I'm sure the guy with the ZL1 Camaro was like "WTF...?".
I'll add more pictures later, but check out the before / after photos-- Holy brake dust!
