This weekend was the first test of my 911 in wide-body, i.e. 930 Turbo configuration. It had been my belief that the reason my car, or any narrow body 911 on a national scale could not keep up with the BMWs in NASA GTS-3 was due to the much larger footprint they enjoy. My brakes were far to hard to modulate with too much front bias so I addressed both problems are here are the results:
The following was done -
Added Turbo sized flares and 9x11x18 wheels, up from 8x9x18
Changed to Hoosier R6 in 245/285 from BFG R1 225/265. (Note that the Hoosiers are also a little shorter, providing better gearing)
Added large carbon fiber rear wind element to rear
Installed twin master brake cylinders in place of single stock turbo MC
The results were nothing short of amazing. My previous best at MSR-Cresson on the 1.7 mile track was 1:24.2. Here is what happened:
Session 1: My best time was 1:21.9 on sticker tires that had not been
heat cylcled or scrubbed. I actually thought I was taking it easy,
learning the new car and being gentle on the new tires but the time
came down quickly.
Session 2: A friend, and better driver, took the car out and put down a 1:20.9 as he went all out on the once heat cycled tires.
We then adjusted the brake bias slightly more to the rear to see what would happen.
Session 3: I drove and it felt like the track gave up a bit. It was
96 degrees out and the session started at 2:30pm so it was pretty
greasy. Best I could do was 1:22.9 but I attribute that to the
track. Looking at the tires I also noticed that there was a fair
amount of graining on the passenger rear so they were not at their
best compared to the morning. Brakes felt great, though the bias will
take some getting used to. My old set up was overly front biased and
a real problem so its nice to have that licked but feels a bit
strange because its new. Its was also a bit more difficult to rotate
under trail braking, so I need to work on my driving style or
potentially go back to the original setting.
Only downside is the effort. Big tires and no power steering is a
work out. Certainly managable in a 20-30 minute sprint, but longer
races and enduros will be a challenge.
Best thing I have done to the car since the 993 engine install! Apparently you can buy time!!
