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Discussion Starter #1
Seeing as i plan to throw the MR2 onto at least Thompson Raceway this year, i fear that the "better rotors and pads on factory turbo brake setup" may not be the safest thing. While i used to think transfer braking and the cheap upgrades might be alright, since everything else i've been putting the screws to has out of this world race-grade brakes (TTRS factory brakes are 8-pot monsters and the GTR is using wolerines bones with up-rated calipers to stop from what i can gather), i plain out dont feel safe on those dinky teacup saucer things. The RS does not weigh that much more, but can't wear anything under a 19' because of the rotor sizing up front... we tested, brakes are better than a Cayman GTS on identical tires (type, not size, i have a boatload of rubber on the porsche). MR2 will never outrun that thing, but it should sure as hell be able to stop better than an AWD rally car dressed up as a well-off racer. If it comes with cup holders, it should not stop in shorter distance than the braced mid engine thing, it just seems wrong somehow :).
I've driven plenty of CC setups, they're really only coming to maturity now IMO, or i guess circa 2018 in the VAG/Lambo/Porsche iteration and Ferarri still has some homework to do ("bedding" is not as gentle a word as it sounds). My current train of thought is that they're cost prohibitive and i actually want progressive brake feel on this platform, i dont need to experience a 60-0-wall-face-thing every time i want to scrub a couple of miles off the speedo. Obviously i have no ABS, only the suspension pieces and calipers came from the JDM donor.
What are some decent options for sharp street performance, track safety, availability during the fauxpocalypse, and driver feel/steering control? Large part of the appeal of this car is the very detailed road feedback it provides, which i'm hoping to keep and enhance while improving performance/reducing fade. What do folks use for pads with these brake setups under "mostly spirited road use" with some track adventures sprinkled in? Obviously i dont want to lay out 10k, but given what brakes do for me, i'm more than willing to pay a small premium for increased chance of survival.
 

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Alex W's Wilwood kit front and rear is awesome for the price point and performance IMO. Especially over early '91-92 brakes, which IMO are not suitable for track usage at 200+ rwhp even with hotter pads.


Good news is you'll get LIGHTER brakes than the '93+ brake sizes, so you get all the suspension and handling feel improvements that come with less unsprung mass.
 

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93 calipers with Supra rotors in front and rx8 rotors in rear vs wilhelm ultralite.

What are the objective performance difference between those two setups?
 

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93 calipers with Supra rotors in front and rx8 rotors in rear vs wilhelm ultralite.

What are the objective performance difference between those two setups?
About 34lb of rotating mass, plus an additional ~14lb of unsprung (non rotating) mass, for starters.

Much better pedal feel due to the fixed, 4 piston calipers vs the stock sliding calipers. (this may be less objective and more subjective, but it's worth noting).

Larger, thicker, and generally CHEAPER pads, available in nearly any compound you can imagine.

The HD vs the ultralite reduces the weight savings by a couple of lb, but increases the size and thickness of the pads, and increases the durability of the rotors.
 

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Discussion Starter #6
Thanks for the advice. Took a look at the kit, and it seems like what i'd want would be the full-sized calipers and pads with the lighter rotors. Is that the going wisdom, or does fade creep faster into the lightweight rotor option through heat-soak?
 

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If you're going to see any real track time, I'd recommend the HD rotors. It's not so much a fade problem (although the ultralight setup will fade a slight bit faster due to higher peak rotor temps), but the HD rotors are far more durable to track abuse.

Street/auto-x usage is fine with the ultra light rotors, and they're like half the cost of the HD rotors. They will crack after ~6-10 track days in my experience though. I did it twice, and both times it was a BIG crack on cool down that had me concerned with rotor integrity for the rest of the day. The HD rotors are a small amount heavier (~1-1.5 lb per rotor ring?), and they're made of a more durable iron alloy that takes extreme temperatures better. I routinely got ~25 track days out of a set of fronts on my front heavy 240SX (same brake setup as Alex W is using here), and it was more using track pads on the street that would wear them out before the cracking at the track would cause any problems.

Either rotor setup has more cooling area than stock rotors, so things will tend to run cooler than stock by a fair margin.

I'm personally going to try out Stoptech 309 Sport pads on Alex W's HD kit and see if it'll suffice as a dual duty street/track setup without changing pads. I know it's a long shot based on previous experience, but it just might work with the occasional cool down lap after ~10-15 mins. But if I need hotter pads for track usage, they're cheap and readily available in the Superlite fitment.
 

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If you're going to see any real track time, I'd recommend the HD rotors. It's not so much a fade problem (although the ultralight setup will fade a slight bit faster due to higher peak rotor temps), but the HD rotors are far more durable to track abuse.

Street/auto-x usage is fine with the ultra light rotors, and they're like half the cost of the HD rotors. They will crack after ~6-10 track days in my experience though. I did it twice, and both times it was a BIG crack on cool down that had me concerned with rotor integrity for the rest of the day. The HD rotors are a small amount heavier (~1-1.5 lb per rotor ring?), and they're made of a more durable iron alloy that takes extreme temperatures better. I routinely got ~25 track days out of a set of fronts on my front heavy 240SX (same brake setup as Alex W is using here), and it was more using track pads on the street that would wear them out before the cracking at the track would cause any problems.

Either rotor setup has more cooling area than stock rotors, so things will tend to run cooler than stock by a fair margin.

I'm personally going to try out Stoptech 309 Sport pads on Alex W's HD kit and see if it'll suffice as a dual duty street/track setup without changing pads. I know it's a long shot based on previous experience, but it just might work with the occasional cool down lap after ~10-15 mins. But if I need hotter pads for track usage, they're cheap and readily available in the Superlite fitment.
The Stoptech sport pads are my current favorite dual purpose pad. Quiet and civilized on the street, and can handle quite a bit of track abuse. I haven't been able to fade them in a 20 minute sessions so far, although I do think I am relatively easy on brakes. I have actually been thinking about swapping them out as my standard pad in my kits, instead of the Wilwood BP20.
 

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Thanks for the advice. Took a look at the kit, and it seems like what i'd want would be the full-sized calipers and pads with the lighter rotors. Is that the going wisdom, or does fade creep faster into the lightweight rotor option through heat-soak?
As Def said, the ultralite rotors won't hold up to track abuse as well, but if you only do one track day per year, then needing to replace them every 6-10 days is still a long time. But a lot of people do prefer the look of the larger calipers, and the rotors are an easy upgrade later. So if you want to save some money up front without compromising on the calipers, that's definitely the way to go.
 

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Discussion Starter #10
If the weight difference is that small, and there's any concern for safety/cracking, i'll probably end up springing for the HD set with the dual-use pads suggested.
What's the ship time looking like nowadays? My MR2 exhaust has been a nightmare - shop tried to source from vivid, who took their money and stopped taking their calls; my GTR is 2 months overdue because of clutch delays due to factory closures, and i'm wondering what the realistic time to delivery would be if i were to order these after getting godzilla back and resetting the automotive budget (hopefully in the next two weeks).
 

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To be clear about the rotor cracking, ALL rotors will eventually crack with enough track use. It's not uncommon for that to be the reason you have to replace them, rather than actually wearing them out. If you are a frequently tracking the car, by all means get the HD rotors, but know that they too will probably crack before you wear them out. It's only a safety issue if you aren't doing the proper maintenance and replacing them before the cracks get too large.

Normally ship time is pretty quick, but at the moment I am back ordered on both brake lines and parking brake cables. Should be not much more than another week on those, but, I don't want to promise anything.
 

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About 34lb of rotating mass, plus an additional ~14lb of unsprung (non rotating) mass, for starters.

Much better pedal feel due to the fixed, 4 piston calipers vs the stock sliding calipers. (this may be less objective and more subjective, but it's worth noting).

Larger, thicker, and generally CHEAPER pads, available in nearly any compound you can imagine.

The HD vs the ultralite reduces the weight savings by a couple of lb, but increases the size and thickness of the pads, and increases the durability of the rotors.
Any estimates on 60 to 0?
 

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Any estimates on 60 to 0?
That's going to depend more on your tires than your brakes. A big brake kit won't necessarily stop you any faster than good condition stock brakes will, once... It's managing the heat generated by repeated braking on a race track where it really shines.
 
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