Porsche 944 Track Car – VIR and Cold Weather

Posted by newhillgarage ⋅ March 11, 2016

VIR. February. What could go wrong? Well, fortunately, not much. Unlike 2 years ago at a Chin event when there was a 2″ snowfall Friday night before the event, this event was actually rather pleasant. Yes, it was 22 degrees when I pulled into the pits at 6:30 am. But my mid-afternoon the temperatures were in the 50’s and very pleasant. And trust me, after doing VIR at 105 in July, I was really enjoying the cool temps.

If you were to review my article about taking 225 pounds of the car, you would know that I was very excited to see how the car performed with its effective 25 hp increase (rule of thumb: 10 pounds less weight feels like 1 horsepower). It may not sound like much but on top of the existing 135 hp at the rear wheels, there was definitely a difference. Although in my first session, the car was very down on power. It turned out that one of the fuel injection harness plugs was not seated correctly.

I was at this DE as sponsored by Tar Heel Sports Car Club (www.thscc.com). They run an excellent event and I try and attend their events when I can. Due to the quirks of the schedule, my first run was mid-morning and my second run was not till after lunch. Anticipating the cold temps, I had put some Kumho Exsta AST tires on the car for the first session. But I what I was really anxious to check out was my 235-18 front / 285-18 rear setup that I had brought, courtesy of the cast off Michelins from my wife’s Cayman. I was still not clear if they would clear the wheel wells during hard cornering. I mounted them on the car during the long break and took it for a short spin on the access roads. No rubbing occurred. Next up was a trip onto the track during the lunch break low speed event for all comers. Much to my embarrassment, I spun the car off the track at Turn 4! I was putting in some violent steering inputs, trying to see if there was any tire rub and next thing I knew I was in the grass. Fortunately for my new 5 pound aluminum bumpers, not contact was made with the tire wall, so I collected myself and motored on. Still no rubbing.

Next was an actual track session with the new tires. Cutting to the chase, I never had any problem with tire rub. Now my suspension is set up with effectively 350 lb/in springs at all 4 corners, so the suspension does not deflect very much. That said, I was modestly surprised that this tire/wheel package would work in a car designed for 225/15’s.

Unfortunately, there was another problem that I had not anticipated. High speed vibration. It was pretty awful on the straights. I came in and jacked the rear of the car up. I really expected to find a flat spot from my little lunchtime 4 wheels off event. But as far as I tell, the rear tires both had a little “hop” in them. This really confused me as I had them Roadforce balanced before the event, which should have spotted the problem. Whatever, I stuck with the tires for the rest of the day and at the end of the day, put the Kumhos back on in anticipation of cold temps again on Sunday morning.

Sunday was a special treat for all the DE participants. We were running the “Grand Course”. It takes the VIR Full Course, and adds elements of the South Course and the Patriot Course to make a very long track. 4.1 miles to be exact. Here is a map:

I really, really enjoyed this configuration! My 944 is pretty boring on the straights but it loves the corners. This course layout is the next best thing to living in the mountains. Plus, if you run off track, you don’t die. Always a plus. I was very polite and consistently gave passing signals to my higher powered trackmates. But thru the twisties, the 944 was loads of fun. I really like this course layout (Oh, I already said that). Unfortunately, rumor has it that VIR management charges a stiff premium to run this configuration. I think the only reason THSCC was able to handle the expense was due to an offsetting rate reduction for running in what was effectively winter. Oh well, I’ve done the Grand Course at least once. Bucket list check mark!