cutting weight makes a much bigger difference going sideways than it does going in a straight line. V3's out of the box won't be the greatest on the track, they're valved more for grand touring. honestly you can have a much better setup for less if you're gonna be tracking that much. i've seen quite a few cases of people ditching KW's for BC's, Fortune 500's and even Megan's w/Swift springs dropping lap times(V3's will ride great on the street though). for the track 18x9 +35 on 265/40's would be good. Enkei RPF1's in those specs weigh in at 17.1lbs and Hankook RS3's are available in those sizes.

how much power are you putting down? any notable weight savings/additions? BBK?

It actually takes a bit of work to make these offsets/widths work w/full sized tires, what sized tires are you looking to run?