I made 380WHP & 420WFT/LB of torque with Cobb E-30 map. When it was warm out my 255/35/18 michelin pilot super sports couldn't break my rears loose even with a first gear roll-out pull.
The mechanical grip on these cars are just incredible.
My friend making 350WHP on his Twin-Turbo 300ZX with coilvers & 275/35/18's Falkins on the rear can break loose in 2nd gear straight line no issue with just moderate throttle. I drove his car and going back to mine I couldn't believe the amount of mechanical grip that our Bimmers have. And I'm not exaggerating at all about any of this.
Cant beat 10+ years of suspension geometry & engineering.
Go with a 6MT & RWD. You won't regret it!
ESPECIALLY later on down the line if you plan on dropping catless DP's (easier on non-awd models) [and you will believe me], or all out with an upgraded turbo setup. (You wont have to deal with funky 5th gear 6AT issues, or power-holding capabilities of the transmission. Upgrade clutch with 6MT & DONE!)
Also, you 335i guys are extremely lucky with bigger wheel arches and a better stock offset. You can easily fit 245's up front & 275's in the rear. And if grip is what you are looking for then nothing gets you better grip than upgrading what actually makes contact onto the road.
My little 1's perfect fitment is 225/255. 235/265 is possible but is pushing it.
Last edited by sparkyblue; 11-20-2012 at 08:41 AM.