Tuesday, April 10, 2012

NASA March Madness @ VIR

My lap times are going the wrong way.  Call it fear of aggravating my appendectomy wounds, call it fear of the damp conditions, the result is the same: I'm getting slower.  And data is telling me something I really didn't want to know.  It's the wing.

In February, I set an aggressive angle on the trim tab because I could only get the foil to go flat, even at max elevation. This was due to the slope of the trunk and limited adjustment options on the wing itself. I couldn't get the car past 114, which was off its previous best of 118mph and clearly not working.  So I dialed the tab back to 50% and got a little better performance without losing grip.  But I'm still almost 2 full seconds off last season's pace.

I adjusted shift points, drove harder through South Bend than I ever have before, and took 3 full seconds off my braking PER lap.  The car rockets up to 90mph like it's been shot out of a cannon, but hits an aero wall.  Acceleration graph comparisons over distance show a dramatic fall-off at 90, so it's clear I need to dial that trim tab down even further, but I don't know that it will be enough to keep the rear end planted and regain any time.

In spite of the high 2:21's, though, I was still able to eke out a win both days, finishing just 0.3 seconds ahead of second place on Saturday, but cementing a firm lead on Sunday before the rain ruined the afternoon.

Overall it ended up being a very good weekend, and I have to thank Hoosier for their generous contingency policies, but it's clear I have some work to do to get the car to go fast again.

I'm currently debating replacing the wing with a rear diffuser and going back to my beefier sway bars.  The stock ones do not feel planted at all, and they're much noisier when pushed to the limits.

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