Question: When do I need a big brake kit?
#1
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Question: When do I need a big brake kit?
Answer: When you can do this to Carbotech XP10s in 100 miles.
I was running XP10s because I did this to the last bit of my XP12s on Saturday:
Replacing the fronts with 11" Corrado rotors and M-tuned brackets, going to XP12s front and rear, and ordering a Tilton proportioning valve. My 1.8 brakes were fine for the vast majority of drivers, but with the added downforce on my car and my driving capabilities coming up to meet the car this weekend in a big way, the brakes finally waved the white flag.
This isn't a critique of Carbotechs in any way - these pads worked very well both days, with a little fade in the last sessions of each day. You can't expect the pad material to make much of a difference when the heat in the brakes severely warps the backing plates.
I was running XP10s because I did this to the last bit of my XP12s on Saturday:
Replacing the fronts with 11" Corrado rotors and M-tuned brackets, going to XP12s front and rear, and ordering a Tilton proportioning valve. My 1.8 brakes were fine for the vast majority of drivers, but with the added downforce on my car and my driving capabilities coming up to meet the car this weekend in a big way, the brakes finally waved the white flag.
This isn't a critique of Carbotechs in any way - these pads worked very well both days, with a little fade in the last sessions of each day. You can't expect the pad material to make much of a difference when the heat in the brakes severely warps the backing plates.
#3
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Christ.
What/where can I get info on this prop valve?
I've got 1.8 stuff sitting on my parts car...Might have to man up and follow your lead.
What/where can I get info on this prop valve?
I've got 1.8 stuff sitting on my parts car...Might have to man up and follow your lead.
Last edited by miatamania; 03-24-2009 at 08:51 AM.
#5
fwiw
Pad wear like that is atypical. That's caused by a variety of issues, but there is definitely a problem when you get uneven wear top to bottom. The only uneven wear that's normal is on the leading edge of the pad. And we usually tapered the pad to minimize that. Think about tire wear, then look at your pad. You're not using but maybe half of the pad and inefficiently at that. Uneven wear like that brings a quick end to a brake pad due to overloading in one area creating excessive heat and wear.
The Miata brakes are lot better than they get credit for. Cooling and proper pad material ftw. I've cited this example numerous times, but it's a good example. We ran a four hour enduro at Daytona in a 99 that weighed in at 2350# w/o driver. We were on the massive spec hoosier tire (225-45-15), with hawk blues, stock calipers, brembo rotors and two brake vents/hoses running from the mouth to the calipers. Running a 4.10 rear the car was just over 7k into the bustop chicane brake zone and a bit higher into the T1 brake zone. So not a turbo car, but certainly turbo speed.
Car had 1/3 pad material left at the end of the race and I can say that for at least the first two hours of the race (my stint) the brakes were used to their max. Brakes are no different than anything else on the car- they require tuning, adequate material/parts, and proper (driver) application.
I'm not saying bigger brakes won't fix your problem, I'm saying that your current brakes are probably operating at about half their potential.
The Miata brakes are lot better than they get credit for. Cooling and proper pad material ftw. I've cited this example numerous times, but it's a good example. We ran a four hour enduro at Daytona in a 99 that weighed in at 2350# w/o driver. We were on the massive spec hoosier tire (225-45-15), with hawk blues, stock calipers, brembo rotors and two brake vents/hoses running from the mouth to the calipers. Running a 4.10 rear the car was just over 7k into the bustop chicane brake zone and a bit higher into the T1 brake zone. So not a turbo car, but certainly turbo speed.
Car had 1/3 pad material left at the end of the race and I can say that for at least the first two hours of the race (my stint) the brakes were used to their max. Brakes are no different than anything else on the car- they require tuning, adequate material/parts, and proper (driver) application.
I'm not saying bigger brakes won't fix your problem, I'm saying that your current brakes are probably operating at about half their potential.
#6
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M2, I'm fully aware it's atypical wear. I did this at Laguna Seca which is notorious for being very hard on brakes. My aero setup doesn't help at all. The inside-outside uneven wear came from the outer pads, which had the claws of the caliper dig into the backing plates and twist them out of proportion. The inner pads were better, but the piston itself actually pressed into the pad so hard that it slightly warped that one too. I used most of the inner pads and maybe 70% of the outer pads.
Ducting is on my list of things to-do. The prop valve will make a big difference as well; the rear XP10s look nearly brand new still, an indication of how poor the stock bias really is.
Ducting is on my list of things to-do. The prop valve will make a big difference as well; the rear XP10s look nearly brand new still, an indication of how poor the stock bias really is.
#10
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Speaking of wine and cheesers...
I took a drive to a local winery this weekend with the girlfriend to drink some free wine and so she could buy some bottles to replenish her supply. As we were getting ready to leave, an older guy and his wife approached and asked about the car. He said he had one as well, blah blah. I told him I wish I would have got over the "*** car" stigma sooner and actually driven one a few years ago, because I love the way the car drives (other than a lack of power which is currently being addressed). He and his wife were like "Oh really? We've never heard of thm being called that." After they left, my GF asked "What rock have they been hiding under to not know that?"
I took a drive to a local winery this weekend with the girlfriend to drink some free wine and so she could buy some bottles to replenish her supply. As we were getting ready to leave, an older guy and his wife approached and asked about the car. He said he had one as well, blah blah. I told him I wish I would have got over the "*** car" stigma sooner and actually driven one a few years ago, because I love the way the car drives (other than a lack of power which is currently being addressed). He and his wife were like "Oh really? We've never heard of thm being called that." After they left, my GF asked "What rock have they been hiding under to not know that?"
#16
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Cause I was cheap, got a huge discount since I sold the pads and was told they'd be fine for a 2000 lbs car at 170rwhp. Even the rears were at the backing plates.
I now have a set of xp10/xp8s, the Corrado rotors and a Wilwood proportioning valve for this season.
I now have a set of xp10/xp8s, the Corrado rotors and a Wilwood proportioning valve for this season.
#18
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mini note:
brakes (like clutches) are energy conversion devices.
brakes convert kinetic energy into heat.
in order to work, you have to be able to transfer heat effectively from the brake pad interface to the atmosphere.
if you can't get the heat OUT of the brakes, they are not effective.
so while you might think bigger brakes = bigger heat sinks, you'd be right but you'd also be missing the point that you still need to transfer heat from the disc to the atmosphere.
GET SOME DUCTS ON THAT THANG.
brakes (like clutches) are energy conversion devices.
brakes convert kinetic energy into heat.
in order to work, you have to be able to transfer heat effectively from the brake pad interface to the atmosphere.
if you can't get the heat OUT of the brakes, they are not effective.
so while you might think bigger brakes = bigger heat sinks, you'd be right but you'd also be missing the point that you still need to transfer heat from the disc to the atmosphere.
GET SOME DUCTS ON THAT THANG.