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wstar · 08-03-2014, 12:00 PM

The Race 4 Charity event at MSR Houston was awesome! We had a bunch of guys from the Houston Z's crew show to participate and/or hang out, so there were lots of Z's in the parking lot

The TT

Big thanks to MSR Houston for putting on such a fun event. I ran in what they labeled the "Australian Pursuit Time Trail" group. Now that I understand it a little better: it's basically the road-course version of a bracket race for cars/drivers with wildly varying lap times, with all the cars out together. You set a qualifying time, then they release everyone slowest cars first, spaced out such that they would theoretically all meet at the finish line at the end of the last lap. The winner is basically the guy who finishes first-ish, but what that really boils down to is maintaining as close to your qualifying time as you can in spite of traffic. If you have any laps under your qualifying time, you get penalized for those.

I didn't even bother trying to game the lap-time system; I just went out there and hauled and tried to pass everyone I could safely pass

. I think most of the rest of the drivers were having fun with it too; they said in the first of our two race sessions, all but 3 cars broke under their qualifying time

Hawk DTC-70/60 pads

I bedded these pads on-track during our morning practice session, using my Hankook RS-3's and progressively bringing up my braking force over a few laps. Then I ran a couple more hot laps before bringing it in, which was probably less than ideal. Still, they seemed to bed well and leave a consistent transfer layer, and worked great for the following two sessions. They were pretty good at modulation, had a nice high torque, and the initial bite was in a nice reasonable range where it's easy to control but still grabs the car.

My only complaint is that in the final session of the day (Race 2), I had what I think were some heavy ABS ice-mode issues. It was a little surprising because I didn't have it all day before that, but I think it was just the heat buildup throughout the day finally got the brakes up to a critical temperature where the front DTC-70's torque fell off just enough that the rear DTC-60 were grabbing better, which then triggers the ABS system to shoot itself in the head. I was able to pump the brake pedal to reset the ABS, at which point the pads themselves stopped the car fine, but the inherent delays in the process of reacting to and dealing with ice-mode would inevitably send me a good bit deeper into the corner than I intended. After about 4 of those incidents within 2-3 laps I went ahead and pitted in early - didn't want to risk hitting that ice mode in close traffic and taking out someone else's car.

I still need to tear down the car this week and make sure nothing's physically wrong with any of the pads that could have contributed, but barring that I'm assuming it's our ABS controller's fault and not the pads. Probably for this car with Hawk DTC, you need a bigger gap in front/rear pad torque to avoid it.

Tires

I ran 3 full-on hot sessions on the Conti GT-O slicks (that I did a light scrub-in session on a few weeks ago). I love these tires, but coming from street tires I'm sure I'd love any decent slick. Strangely, just looking at wear pattern on the tire, they seem to want slightly less rear camber than my RS3's do (could also mean I'm just not pushing the rears as much as they're capable of, relative to how I was doing on the RS3?). I set my cold pressure before the first session at 20 in the rear and 21 in the front, and they felt great and the wear pattern looked ok, so I just left it alone the rest of the day. I'll micromanage temps and pressures some other time, for now I'm just enjoying them and getting used to them

My best lap times from the first session (practice) on RS3 to the second session (qualifying) on the Slicks dropped about 3 seconds (~1:51.xx -> ~1:48.xx).

Video
I'm planning to upload the full session video for both of the Race sessions later, but they're huge and take forever to process and upload, so it might be a day or two. For now I just uploaded lap excerpts for my best times on both tires:

RS3 @ 1:51.34 in Practice - https://www.youtube.com/watch?v=XJRhNQng4y4
Slicks @ 1:48.24 in Qualifying - https://www.youtube.com/watch?v=hedmaplytNI

08-03-2014, 12:00 PM	#833 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	The Race 4 Charity event at MSR Houston was awesome! We had a bunch of guys from the Houston Z's crew show to participate and/or hang out, so there were lots of Z's in the parking lot The TT Big thanks to MSR Houston for putting on such a fun event. I ran in what they labeled the "Australian Pursuit Time Trail" group. Now that I understand it a little better: it's basically the road-course version of a bracket race for cars/drivers with wildly varying lap times, with all the cars out together. You set a qualifying time, then they release everyone slowest cars first, spaced out such that they would theoretically all meet at the finish line at the end of the last lap. The winner is basically the guy who finishes first-ish, but what that really boils down to is maintaining as close to your qualifying time as you can in spite of traffic. If you have any laps under your qualifying time, you get penalized for those. I didn't even bother trying to game the lap-time system; I just went out there and hauled and tried to pass everyone I could safely pass . I think most of the rest of the drivers were having fun with it too; they said in the first of our two race sessions, all but 3 cars broke under their qualifying time Hawk DTC-70/60 pads I bedded these pads on-track during our morning practice session, using my Hankook RS-3's and progressively bringing up my braking force over a few laps. Then I ran a couple more hot laps before bringing it in, which was probably less than ideal. Still, they seemed to bed well and leave a consistent transfer layer, and worked great for the following two sessions. They were pretty good at modulation, had a nice high torque, and the initial bite was in a nice reasonable range where it's easy to control but still grabs the car. My only complaint is that in the final session of the day (Race 2), I had what I think were some heavy ABS ice-mode issues. It was a little surprising because I didn't have it all day before that, but I think it was just the heat buildup throughout the day finally got the brakes up to a critical temperature where the front DTC-70's torque fell off just enough that the rear DTC-60 were grabbing better, which then triggers the ABS system to shoot itself in the head. I was able to pump the brake pedal to reset the ABS, at which point the pads themselves stopped the car fine, but the inherent delays in the process of reacting to and dealing with ice-mode would inevitably send me a good bit deeper into the corner than I intended. After about 4 of those incidents within 2-3 laps I went ahead and pitted in early - didn't want to risk hitting that ice mode in close traffic and taking out someone else's car. I still need to tear down the car this week and make sure nothing's physically wrong with any of the pads that could have contributed, but barring that I'm assuming it's our ABS controller's fault and not the pads. Probably for this car with Hawk DTC, you need a bigger gap in front/rear pad torque to avoid it. Tires I ran 3 full-on hot sessions on the Conti GT-O slicks (that I did a light scrub-in session on a few weeks ago). I love these tires, but coming from street tires I'm sure I'd love any decent slick. Strangely, just looking at wear pattern on the tire, they seem to want slightly less rear camber than my RS3's do (could also mean I'm just not pushing the rears as much as they're capable of, relative to how I was doing on the RS3?). I set my cold pressure before the first session at 20 in the rear and 21 in the front, and they felt great and the wear pattern looked ok, so I just left it alone the rest of the day. I'll micromanage temps and pressures some other time, for now I'm just enjoying them and getting used to them My best lap times from the first session (practice) on RS3 to the second session (qualifying) on the Slicks dropped about 3 seconds (~1:51.xx -> ~1:48.xx). Video I'm planning to upload the full session video for both of the Race sessions later, but they're huge and take forever to process and upload, so it might be a day or two. For now I just uploaded lap excerpts for my best times on both tires: RS3 @ 1:51.34 in Practice - https://www.youtube.com/watch?v=XJRhNQng4y4 Slicks @ 1:48.24 in Qualifying - https://www.youtube.com/watch?v=hedmaplytNI __________________ 7AT Track Car! Journal thread / Car setup details Last edited by wstar; 08-03-2014 at 12:16 PM.