View Single Post
      06-09-2012, 11:09 AM   #119
Brigadier General

Drives: Jerez Black E90
Join Date: Sep 2007
Location: STL

iTrader: (3)

So I've got a couple weeks until my next event (which will be the first event on the new MCS 2-way Stock-class dampers) and I got bored and wanted to check my math on curb weight, so I threw the Hoosiers on the car and weighed the car. I also test-fitted 315/30-18's on the front...

The car weighed 3522 with about 2-3 extra gallons of gas in it, but otherwise set up how I would compete in it with all trunk junk and spare change removed. I can autocross without any fuel starve until well below the 1/4 tank mark, the car was at about 3/8 tank. So figure conservatively there was 12 lbs of extra weight in it. This all makes sense considering I was figuring 3500 with 1/4 tank on the stock shocks and now with the ~8lb weight gain I'm at about 3510 with 1/4 tank.

The car could lose some in the wheels as my TR MT1's are not the lightest choice out there and I'm using ~1lb's worth of spacers. With some TE37SL ET22 rears, which wouldn't need spacers, and some kind of lighter 18x8.5 there might be another 5-7lbs in the wheels. There is also room to lose in the exhaust, and I'm going to try running without the M Performance muffler (just connecting pipes) to see if I can make sound. The canister weighs about 22lbs. So my less than ideal car could, in theory and with more $$$, get to ~3480 competition weight. A car without the cold weather and premium packages might be another 10-20lbs lighter, figure another 25lbs lighter for an E92 and you're probably looking at 3425 or so for a full-tilt no-compromises build, maybe even lighter if 11+ cars with manual seats are lighter (I suspect they aren't because of the auto stop/start system, but haven't seen data yet).

So on to the silliness:

One of the advantages of using the stock spring perch location is the great tire clearance, and the MCS dampers are a little smaller OD than the stock dampers so there's more room now. The 315's fit on the front with 18x9.5ET35 and 12.5mm spacers, but they stick out about 1/4" from the fenders. This *might* tuck in as the car rolls but I'm not going to find out. They also rub slightly on the back of the fender liner, but they fit, and don't rub at all in the front of the fender. So a little relieving of the fender liner with a heat gun or whatever, and more camber would probably make them fit comfortably, *without cutting the fenders ! This could be big in a more modified class as you can go pretty wide with the tires without making the car wider. You could even do this with coilovers with the right spring and perch. As long as I don't have holes rubbed in the fender liners a little "rubbin' is racin'" is legal in Stock, so it might even work in Stock class. Pretty crazy. Wonder what they would look like on 8.5" wheels? Maybe we'll find out...

Last edited by Richbot; 06-09-2012 at 04:11 PM.