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Old 04-27-2010, 07:12 AM   #41
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I've got XP8s on the car right now as well for autox. Having the same issues. Just cannot get them hot enough til the very end of the run to get any good use out of them. But I fade my HPS at autox so i'm not sure what to do at this point.

Hawk HP+ perhaps?
XP8 is a track pad.
For autox, use properly bedded in stock pad.
I use ceramic (Bendix) pads. Good cold stops, great warm, lousy hot (track).
The great benefit of ceramics is little to no dust.

If you want a good all-around pad, and don't care about the dust, use "Plain Jane" semi-metallic. Autozone has Duralast for $25 per axle.

Track pads, like XP8, are for track only. Swap the rotors and pads before heading out to the track (or, better yet, right AT the track), and swap street setup before going home. This way, street rotors stay with street pads, and the two compounds shall not mix. (No, it doesn't matter if you mix the rotors).

STOP trying to figure out which pad will stop better on the autox course. Even on a 2-minute course, run on an abandoned airstrip, I've never seen the brakes even get to what could be called "luke warm".

Street pads for autox.
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Old 04-27-2010, 12:59 PM   #42
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^^ I don't know how much it helps, but on the drive from the staging area to the line, I'll brake boost/roll brake to get some heat in the brakes and the rear tires. It seems to help with the first couple of times I stab the brakes vs. when I don't warm them up.
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Old 04-27-2010, 01:00 PM   #43
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Well I guess i'm going to have to try some 25 dollar cheapo pads for next autox perhaps. The XP8s really aren't that bad though, they're just unpredictable when cold and like to lock up. I shouldn't be wasting them off track anyway.
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Old 04-27-2010, 05:36 PM   #44
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Originally Posted by wayne_curr View Post
Well I guess i'm going to have to try some 25 dollar cheapo pads for next autox perhaps. The XP8s really aren't that bad though, they're just unpredictable when cold and like to lock up. I shouldn't be wasting them off track anyway.
Regular street pads are best for autocross. Hard braking should be seriously avoided as much as possible if you want to be fast on an autocross course anyway.

I’ve had good luck with Axxis ultimates. They are a ceramic carbon mix and seem to have good feel and the dust isn’t so corrosive as the pads with metal in them, the dust cleans up easily, and they are relatively cheap.

I have found the Carbotecs really don’t like sharing the rotor surface with any other pad compound and are a bit finicky about getting a proper bed in procedure. I have been swapping between Cobalt frictions for track however and other compounds for street and autocross use and the Cobalts just clean up the rotors and don’t leave a transfer layer behind that messes with other pads The Cobalt’s also don’t require any bed in before they just work as the rotor is relatively flat..

Bob
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Old 04-27-2010, 05:38 PM   #45
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Originally Posted by wayne_curr View Post
Well I guess i'm going to have to try some 25 dollar cheapo pads for next autox perhaps. The XP8s really aren't that bad though, they're just unpredictable when cold and like to lock up. I shouldn't be wasting them off track anyway.
Regular street pads are best for autocross. Hard braking should be seriously avoided as much as possible if you want to be fast on an autocross course anyway.

Iíve had good luck with Axxis ultimates. They are a ceramic carbon mix and seem to have good feel and the dust isnít so corrosive as the pads with metal in them, the dust cleans up easily, and they are relatively cheap.

I have found the Carbotecs really donít like sharing the rotor surface with any other pad compound and are a bit finicky about getting a proper bed in procedure. I have been swapping between Cobalt frictions for track however and other compounds for street and autocross use and the Cobalts just clean up the rotors and donít leave a transfer layer behind that messes with other pads The Cobaltís also donít require any bed in before they just work as long as the rotor is relatively flat.

Bob
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Old 04-27-2010, 05:39 PM   #46
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I've always ran HPS on my AutoX cars. The only hard breaking is into the stop box. And the HPS with nice rotors work well. They won't fade because you're only breaking hard into the box, and then they have a chance to cool down while you're in grid.
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Old 04-27-2010, 05:51 PM   #47
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I've always ran HPS on my AutoX cars. The only hard breaking is into the stop box. And the HPS with nice rotors work well. They won't fade because you're only breaking hard into the box, and then they have a chance to cool down while you're in grid.
Sorry, but I'm not a fan of the Hawk HPS for autox (Subarus, MR2s, Miatas). I really like the HP+ though. Also, FWIW, the Axxis Ultimates were good to me for my first few years of autox.

Then again, I've got a 1.8 with ABS and SS lines. Results will vary.
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Old 04-27-2010, 06:06 PM   #48
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To each their own. I'm currently using HP+ myself.

Bob, how are those Cobalts on the track? What compounds to you use and are you running Wilwoods or stock brakes? I saw your cooling ducts, I'm going to do something very similar utilizing the ISC brake ducts.
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Old 04-27-2010, 07:04 PM   #49
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I'm currently running axxxis ult. as well
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Old 04-27-2010, 09:58 PM   #50
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Huh, Bob's setup maybe combined with the 1.6 fronts like Chris may be my way...Axxis Ult for autox then Cobalt for track.
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Old 04-27-2010, 11:04 PM   #51
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Huh, Bob's setup maybe combined with the 1.6 fronts like Chris may be my way...Axxis Ult for autox then Cobalt for track.
Is cobalt available for single piston calipers?
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Old 04-28-2010, 05:42 AM   #52
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One other thing that can induce big understeer is the differential. If you have a very tight diff it wants to push the front end wide when you turn in. It refuses the let the inside wheel slow down. I know my Tomei Traxx 2 way had me upping the rear swaybar from soft to medium and changing the dampers from 6/10 off full hard front/rear to 6/8. That brought me back to neutral for circuit racing.
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Old 05-03-2010, 02:32 PM   #53
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My biggest issue of the day was the tight slalom. My little 5'2" girlfriend had an even harder time muscling my non-power steering car around. Stock miatas with power steering where 2+ seconds faster than us (one of them on snow tires) through the course. Now, i will admit that the drivers need more work for sure, we're slow drivers, but I think a lot of it has to do with power steering, or atleast the power steering ratio. I drove a 92 stock on the course and could not believe how quickly you can toss it around cones with the better steering ratio.
How tight was this slalom? I go back and forth between two cars, one with a manual rack and a power rack, and honestly can hardly tell a difference. Yeah, you need to turn the wheel slightly more, but it's not any more difficult.

If you depower a power rack, then it'll just require more "muscle", but you won't have to turn the wheel as much.

I'd be more inclined to say that you're having trouble because of a balance issue, crappy springs/shocks, etc. Is your front sway bar binding? That can increase steering effort.
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