Hi John. It was a really fun week.
Turn 7 is good because you want to drive deep into that brake zone, and if you overshoot there is plenty of run off. Turn 10 is my favorite for setting bias because it is not bumpy. I am threshold at turn 17, but a lockup deep in the brake zone on that turn is dangerous, so I like to figure out the bias before high pressure braking there. Turn 3 is OK but a little dangerous. You could brake early there, lock up, and recover in time, but if you brake very deep there and lock up you might hit the wall. It is important to get off the brake immediately when you lock up (and then get right back on it as soon as you recover) whether or not you are setting up bias. The more you test lockup, the faster you get at recovery so it is a good drill to practice.
I believe the track record at Sebring in an SR3 1500 is 2:06 (Gustavo Rafols) which is unbelievable. My best time for the week was 2:10.46 in an SR3 1500. Tom Gladdis did a 2:02 today in an SR10; I would imagine he could get down to 2:00. You would do fine in the Winterfest races. Some SR10s were doing 2:09 and slower laps. The fastest time in the RS1 class, which is also the class for SR8 and SR10, was 1:58 flat by Jon Field in a Ligier LMP3.
@davidf That's great information about braking pressure and markers thanks. I'm back in the shop now, and have finished getting the car ready for a Sebring event in mid-February. I've dialed the bias up to 60% and have lots of data recording (both AiM and MoTeC) to have a close look at my braking performance. I've also upgraded the car from 280mm to 300mm brakes, though that might hurt performance as much as help it. We'll see, and I'll post up some data after the event.
I'd really like some high-fidelity speed data on the front wheels (I have tire pressure and temp data) so I can see lockup in analysis. I have that for both rear wheels (50 points per revolution) but the most I've seen anybody do up front is 4 using the wheel alignment/brake hat bolts. Do you see lockup by feel/vision/hearing in real-time? Or have you found a way to see that in data?
Thanks also for the lap time data. That is good to know.
Does anybody still run an SR8 in Radical Cup?
Do you see lockup by feel/vision/hearing in real-time? Or have you found a way to see that in data?
I go entirely by feel to determine whether the fronts or rears are locking. You can feel the difference in your hands and body whether it is front or rear. It just takes a little practice, but if you never try then you won't know the limit of braking and you won't be able to dial in the bias. The instant you lock up, you need to get off the brakes sufficiently to get those wheels spinning again, but not so much off that you don't make the turn.
Does anybody still run an SR8 in Radical Cup?
Not that I aware of, but you certainly can. The SR10 has a speed advantage on long tracks. At a track like Barber, the SR8 is probably just as fast and in fact the SR3 is nearly as fast.
