Let's talk about brakes!

[sperry]

Originally Posted by BOO

Question: Do these Goldies fit on an STi? Remember when I told you about my cousin in TX who bought a White STi? Well he likes the JDM look .. so I was wondering if these fit the Sti?

The MY98 "goldies" are the gold rims that came on the '98 RS here in the states, so they're not JDM. They're also only 7"x16" rims, so they won't fit an STi either.

[Dean]

I didn't mean to sound like a jerk yesterday, sorry if I did....

Originally Posted by sperry

Been there already. In fact I have 3 unopened bottles in my garage right now. However, I've found that with the low *wet* boiling point, my brakes tend to fade quickly unless I flush (not just bleed) the system before every autocross. The Motul just seems to hold up better over several events.

People don't realize how hard it is to boil fluid in a street car. In about 99 percent of the brake fade instances, the problem is pad/rotor related. In our climate it should not be necessary to do more than bleed a couple ounces per corner before/after each event unless you run with to thin a pad so heat transfers to easily.
What do your rotors look like, and when was the last time they were turned?

Originally Posted by Sperry

I've already gone to Axxis Ultimates (I heard horror stories about the EBCs requiring new rotors with every other set of pads) and StopTech slotted rotors (since I wore the bejesus out of the stock rotors) as well as SS braided lines.On the Auto course *the car friggen stops*. And I have virtually no fade over most courses (Atwater's the big exception). However brake feel is terrible. My pedal is mushy and I can get it to travel all the way to the floor during hard braking, which means my foot is too far past the gas to easily heel-toe.

First, I've got dibs on your old stuff if you decide to upgrade, and somebody can use .
Most people forget rotors are a consumable item, just like pads, This should be a major consideration in selecting a brake system. And any performance or race pad will eat a rotor faster than stock pads. Unfortunately, nice thick directional vaned rotors are fairly expensive.

IMHO you should not experience fade with performance pads during an autocross, and only slightly likely with stock pads. There just is not enough heat involved.

Originally Posted by sperry

Then there's the fade issue on track. I wasn't really pushing at all at Fernely, and just trying to haul the car down from 80 to 20 mph a few times was fading the brakes. Now I know it's possible to get the stock brakes to have zero fade (Gary Sheehan ran a USTCC race on stock brakes!). It requires very agressive/high temp pads, crazy hi-temp fluid, and active cooling ducts. The problem is that the heat sink is so small all that heat gets into the seals, bearings, etc. Gary was replacing his wheel bearings after *every* race and his tierods after every two, since he was boiling the grease in there! Not to mention the brakes themselves were baked clean of all rubber and seals.

Any performance brake system, stock to extreme requires a rebuild every year or so IMHO. This is just a reality of the temps we are talking about. Dust seals a re nice, but likely to get crisp and will likely need replacement as well, so I'm not sure they are a big deal on a performance system. My Wilwoods don't have them, but the Brembos do. Gary also knows how to manage his brake budget, and neither of us are driving at his level.

Originally Posted by sperry

My primary goal however, is to come up with a better brake feel. You're right about not needing to brake as much as you might think (though I'd suggest most people learning to AutoX don't brake enough). I'm not necessarily looking for more stopping power out there, I just want some confidence in my braking system. I want a stiff pedal that gives me an easier position for heel-toe. And I figure, if I'm spending money to achieve that, I might as well get something that's going to fade less, and stop faster, right?

Cliff Notes: I've already tried all the affordable ways to upgrade the brakes and the feel still isn't what I want, so I'm looking to upgrade primarily for feel, but since I'm paying I might as well get less fade and more stopping power.

How does your setup feel on the street? One of my issues with the WRX is what appears to be a loss of brake boost. Debbie also reported this, have you experienced this? Not that it is the issue.

I agree newbies often brake to little, or to much to late.

So how about some usefull information.

The AXXIS may not be up to the challenge. You might try some R4s or HPpluses for AutoX or R4s for track before you give up on your current system. I do like the ATE fluid, especially because you can get two colors so you can tell when you have purged the system.

Rotor diameter is what everybody talks about, but don't believe it. My Wilwoods are identical in diameter to stock, but much thicker and directional vaned and are incredible compared to stock in all respects. My Brembos which are bigger rotors and cross drilled do not stop as well as the Wilwoods. IMHO Thicker is better!

Cross drilled turns the rotor into a cheese grater, and eats pads like they are going out of style. Flat are what most raceers use but they aren't as pretty. Sloted may have a minor ability to out gas better, but BBQing your pads may be the best way to prevent that. So my suggestion is go flat. Any brake kit that doesn't offer a flat disk is not for racing IMHO.

I'll take a look at some of the WRX options and give you some suggestions.

I'll be back Sat. if you want to talk instead of type...

[sperry]

Originally Posted by Dean

I didn't mean to sound like a jerk yesterday, sorry if I did....

?? I never though you sounded like a jerk! You post was one of the most informative posts regarding the stock WRX setup. In fact it's all the stuff I learned the 1st time around when I decided my brakes could use some help, so even though it's repeat info for me, I'm sure a lot of other people that haven't looked at brake upgrades will find it useful.

Originally Posted by Dean

People don't realize how hard it is to boil fluid in a street car. In about 99 percent of the brake fade instances, the problem is pad/rotor related. In our climate it should not be necessary to do more than bleed a couple ounces per corner before/after each event unless you run with to thin a pad so heat transfers to easily.
What do your rotors look like, and when was the last time they were turned?

I'm not so sure I'm actually boiling my fluid. I know when I bleed 'em I rarely see bubbles in the system. However, I do know that as time goes by, my pedal gets softer and softer, worse so if I've been autocrossing. The Motul seems to "soften" slower, i.e. I can go longer before the soft pedal pisses me off to the point I swap the fluid.

As far as my rotors, I've got the slotted StopTech stock replacements (I believe they're actually DBA rotors). And they look *great*. They've been on there since the last 4 weekends of autocross last season, so that's about 8 events and 10,000+ miles, and they're still looking pretty new.

Originally Posted by Dean

First, I've got dibs on your old stuff if you decide to upgrade, and somebody can use .
Most people forget rotors are a consumable item, just like pads, This should be a major consideration in selecting a brake system. And any performance or race pad will eat a rotor faster than stock pads. Unfortunately, nice thick directional vaned rotors are fairly expensive.

Going with the 4-pots will mean I'm still on the stock rotors, and since the SS lines should work with the 4-pots, the only thing I'd have for ya are some Axxis Ultimate front pads. Right now I've got about 50% left on the set in the calipers, and two sets of fronts in my garage, one set of which I've already offered to Art. If I get the 4-pots, the other sets all yours if you'd like to try 'em out. From what I understand the Ultimates won't grab quite as well as the EBC's, but they preserve the rotors a whole lot longer than the EBCs... or so I've heard. Now then, if I hit up a BBK, then I'll have a set of front SS lines for ya too!

I haven't heard of anyone making thicker stock WRX rotors. I agree that anything that increases mass will help prevent face by sinking heat. Idealy it'd be nice to find some directionally vented, thicker stock diameter rotors to go under the 4-pots, assuming you could get the 4-pots over the rotors.

Originally Posted by Dean

IMHO you should not experience fade with performance pads during an autocross, and only slightly likely with stock pads. There just is not enough heat involved.

As I mentioned, fade isn't really a problem with my current setup at an autoX. Feel is my big issue. Fade is aparent on the track however.

Originally Posted by Dean

Any performance brake system, stock to extreme requires a rebuild every year or so IMHO. This is just a reality of the temps we are talking about. Dust seals a re nice, but likely to get crisp and will likely need replacement as well, so I'm not sure they are a big deal on a performance system. My Wilwoods don't have them, but the Brembos do. Gary also knows how to manage his brake budget, and neither of us are driving at his level.

I don't think I'd like a setup without OEM quality brake seals. Since this is my daily driver, it sees winter roads, and I don't need that crap inside my brakes. As it is, I'm thinking I need to get a set of boots for my coilovers. The StopTechs are known to have great seals, and since they're so beefy I'd guess that even w/ occational tracking the heat won't be enough to wear out the seals for a few years. The same goes with the 4-pots, since they're litteraly OEM on the JDM WRXs... but since that system won't be quite as heat tollerant, I may end up rebuilding those once every 2 years or so.

Originally Posted by Dean

How does your setup feel on the street? One of my issues with the WRX is what appears to be a loss of brake boost. Debbie also reported this, have you experienced this? Not that it is the issue.

On the street, the brakes are pretty decent. The heel-toe alignment issues that bother me on course don't happen on the street since I never really have to press the pedal beyond halfway down. I've noticed the brake boost issues only when left foot braking. Because the booster is engine vacuum driven, getting on the throttle with the brake down kills the brake assist. I've actually thought about pulling the fuse for the booster on autoX days, but I'm not 100% sure what that'll do to the system (or if it's even possible to kill the booster that way... it may be fully mechanical). Any ideas?

Originally Posted by Dean

The AXXIS may not be up to the challenge. You might try some R4s or HPpluses for AutoX or R4s for track before you give up on your current system. I do like the ATE fluid, especially because you can get two colors so you can tell when you have purged the system.

Perhaps I should toss a set of different pads in there just for the hell of it. I'd also like to make sure I'm really flushing and bleeding the system correctly. I'm pretty sure I'm doing things right, but I've never seen it done by someone else... perhaps you've got a better technique. I'd especially like some way to flush the ABS system. (God I hate Subaru ABS...)

Originally Posted by Dean

Cross drilled turns the rotor into a cheese grater, and eats pads like they are going out of style. Flat are what most raceers use but they aren't as pretty. Sloted may have a minor ability to out gas better, but BBQing your pads may be the best way to prevent that. So my suggestion is go flat. Any brake kit that doesn't offer a flat disk is not for racing IMHO.

I don't believe pad outgassing is really an issue... the materials in pads these days just don't boil off like that anymore. Slots can help keep a "cleaner" pad surface (and the look cooler), but it does accelerate pad wear. Cross drilled rotors are a waste of money IMO. The only benefit is slightly less weight (since out gassing is a non-factor). The drawbacks are faster pad wear, and rotors that are much more prone to cracking. Some people claim those holes help cool, and while I agree there's more surface area, I can't imaging they help a lot more than a well designed ventilation system would.

So, I think I'm down to two choices: Subaru 4-pots on stock rotors and a set of RS rims for my existing snow tires (the budget choice at about $1000) or some StopTechs and a set of 17" rims and new snow tires (the insane-o choice at about $3000). Considering both choices should help me with my primary concern: brake feel, and since I'm not going to be tracking my car for any competitive reasons, I think the clear choice is to save $2000 and go with the 4-pots... but 1st I've got to deal with my bearings.

[BOO]

Right... But what I am saying is he likes the JDM look.. Not refering to the MY98 that seem to be the same ..

[Dean]

I'll read your post later, but here is my quick look at the options...

#1 WRX 4 pots.
#2 STI 4 pots
#3 Wilwood 6 pots
#4 Stoptech

Nothing else impresses me.

I am amazed nobody is making a Porsche Monoblock kit.

#1 Did you consider these? Will probably only add feel, but with the Stoptech rotors may be enough, and I thnk you can get them cheap JDM, or CDM used.

Used brakes are actually a great deal... I put S4 rears on my A4 for $250 includingg calipers, brakets and rotors with pads!

#2 I'd look for these used also. I'd like some better data on the rotor thickness. My guess is it is under an inch, and I don't know how good the vaneing is. These may be a good mid price option, but if they are thin, don't bet on super performance. By the way, more air flow in a rotor is more important than mass! Big open spaces between fairly thin directional vanes provide radiator like cooling.

#3 My best bang for the buck option. Huge pad and rotor selection, great calipers, and rotors. These are my stealth brakes I think if you want a look. And the rear kit would make it a killer setup.

#4 Only if you must have dust shields. Don't know about pad options though.

One thing I don't know about the WRX is if the master cylinder is up to all this. If it is the same as the one for the 4 pots, it should be OK I guess.

[sperry]

Originally Posted by Dean

I'll read your post later, but here is my quick look at the options...

#1 WRX 4 pots.
#2 STI 4 pots
#3 Wilwood 6 pots
#4 Stoptech

Nothing else impresses me.

I am amazed nobody is making a Porsche Monoblock kit.

#1 Did you consider these? Will probably only add feel, but with the Stoptech rotors may be enough, and I thnk you can get them cheap JDM, or CDM used.

Used brakes are actually a great deal... I put S4 rears on my A4 for $250 includingg calipers, brakets and rotors with pads!

#2 I'd look for these used also. I'd like some better data on the rotor thickness. My guess is it is under an inch, and I don't know how good the vaneing is. These may be a good mid price option, but if they are thin, don't bet on super performance. By the way, more air flow in a rotor is more important than mass! Big open spaces between fairly thin directional vanes provide radiator like cooling.

#3 My best bang for the buck option. Huge pad and rotor selection, great calipers, and rotors. These are my stealth brakes I think if you want a look. And the rear kit would make it a killer setup.

#4 Only if you must have dust shields. Don't know about pad options though.

One thing I don't know about the WRX is if the master cylinder is up to all this. If it is the same as the one for the 4 pots, it should be OK I guess.

Just to avoid confusion, the "STi 4-pots" I'm talking about are *not* the Brembos that come on the US STi... I don't have $3000. They're twice as much as the StopTechs and don't work quite as well.

The "STi 4-pots" I'm referring to are the same as the "WRX 4-pots". I dunno why people started calling 'em "STi 4-pots", I guess they came on older JDM STis or something. They're actually made by FHI. I guess they still come on non-US WRXs. As far as I know, they're designed for the Master Cylinder that's already on the car. They're also supposed to be mated with a set of 2-pots in the rear, but nobody seems to complain about balance with the stock WRX rears or with the popular H6 rear upgrade.

[AtomicLabMonkey]

Originally Posted by Dean

IMHO you should not experience fade with performance pads during an autocross, and only slightly likely with stock pads. There just is not enough heat involved.

Atwater's nationals-sized courses are about the only place this would possibly be an issue for auto-x around here, and then probably only with stock pads, not good ones.

Originally Posted by Dean

Any performance brake system, stock to extreme requires a rebuild every year or so IMHO. This is just a reality of the temps we are talking about. Dust seals a re nice, but likely to get crisp and will likely need replacement as well, so I'm not sure they are a big deal on a performance system.

I've had the PBR calipers on my fronts for about 3 years now and they're still going fine without a rebuild; the dust seals baked off after a year or so, too and I haven't replaced them. I would guess that PBR's are probably one of the most rugged performance calipers out there though, since they're OEM equipment on Corvettes and (newer) Mustangs.

Originally Posted by Dean

Rotor diameter is what everybody talks about, but don't believe it. My Wilwoods are identical in diameter to stock, but much thicker and directional vaned and are incredible compared to stock in all respects. My Brembos which are bigger rotors and cross drilled do not stop as well as the Wilwoods. IMHO Thicker is better!

Agreed; I think it's mostly about how much iron mass is present in the rotor and consequently the more thermal storage capacity.. the more mass the better, to a certain extent, until you start getting into boat anchor territory.

Originally Posted by sperry

Cross drilled rotors are a waste of money IMO. The only benefit is slightly less weight (since out gassing is a non-factor). The drawbacks are faster pad wear, and rotors that are much more prone to cracking. Some people claim those holes help cool, and while I agree there's more surface area, I can't imaging they help a lot more than a well designed ventilation system would.

Cross-drilling is pretty much retarded, in my opinion. That's pretty apparent after looking in a mechanical design text and seeing the stress concentration factors they introduce all over the rotor. Even gas-slotting introduces stress concentration factors at the sharp interface between the slot and the rotor surface, but nowhere near as severe as drilling holes completely through the entire thing. These are obviously reliability & endurance issues that aren't a huge deal for something like a funded race team since they can just throw cracked parts away & get new ones frequently, but for one of us who's gonna want to install the brakes and not have to worry about them, it's better to just get plain rotors for maximum life (and minimum cost).

Originally Posted by sperry

I've actually thought about pulling the fuse for the booster on autoX days, but I'm not 100% sure what that'll do to the system (or if it's even possible to kill the booster that way... it may be fully mechanical). Any ideas?

I've never taken one apart so I don't know for sure, but my guess is you'd probably have to pull the vacuum line (and cap the booster port & line).

[Dean]

On the stealth I have to bleed the brakes with the car running so fluid passes through the ABS sytem.

According to the shop manual it looks like on the Subaru, that might help, but you may have to force it to sequence the ABS to really flush fluid through it... The manual is not perfectly clear.

More later, back to class.

[sperry]

Originally Posted by Dean

On the stealth I have to bleed the brakes with the car running so fluid passes through the ABS sytem.

According to the shop manual it looks like on the Subaru, that might help, but you may have to force it to sequence the ABS to really flush fluid through it... The manual is not perfectly clear.

More later, back to class.

I think you need some special unit plugged into the OBD/II port to trigger the ABS system to cycle. It's prolly a $3000 part.

[STIwish]

I know this is kinda off the brake topic, but you guys keep mentioning Atwater as a highspeed, heavy braking course... you guys REALLY need to come out in May for the event at Manzanar... its a 2 mile course that I was hitting 100+ on the straights in my WRX last year... I pretty much ate my front RE92s in a single event.. but damn was it fun.

[MattR]

Originally Posted by STIwish

I know this is kinda off the brake topic, but you guys keep mentioning Atwater as a highspeed, heavy braking course... you guys REALLY need to come out in May for the event at Manzanar... its a 2 mile course that I was hitting 100+ on the straights in my WRX last year... I pretty much ate my front RE92s in a single event.. but damn was it fun.

Yeah, that is bordering a Solo1 event from what the people at the Reno SCCA meeting were saying. Fast times!

[JC]

....

[sperry]

There was a huge discussion on NASIOC about brakes, and the general consensus on the Rotoras is that it's what all the ricers run. They're pretty, but don't necessarilty perform that much better.

Considering their website has zero technical specs on 'em, I'm inclined to agree.

Another option that I haven't looked at is the BBK sold by ION Performance. Uses AP 4-pot calipers and 12.2" 2 piece directionally vented rotors and fits under the stock 16x6.5 wheels! Looks like a pretty nice kit, but ION's site is down, so I can't get details.

[STIwish]

Originally Posted by MattR

Yeah, that is bordering a Solo1 event from what the people at the Reno SCCA meeting were saying. Fast times!

Im definitely going again, even if I have to rent an autotragic Neon or something.. its too fun not to.

[sperry]

Okay, as you may have read here: http://www.seccs.org/forums/viewtopic.php?p=12217#12217 I don't need to replace my bearings, but I *do* need some rear brake pads. I'm wondering if I should just get another set of Axxis Ultimates for the rear, or if it's time to try something else.

I've already got a stockpile of Ultimates for the front... would anyone be interested in buying them off me to fund some pad "research"? Art, you still interested? Dean, you wanna give a set a shot, or are you happy with whatever it is you're already running?

And if I go for some new pads, what do you recommend? Hawks? EBC Greens?

Or should I just spend the money I don't have (but was going to spend anyway) on bearings on some FHI 4-pots and new rear pads before Buttonwillow?

[Kevin M]

Originally Posted by sperry

Or should I just spend the money I don't have (but was going to spend anyway) on bearings on some FHI 4-pots and new rear pads before Buttonwillow?

Yes yes yes yes yes. Trust me. 4 pots own.Although, while I too am skeptibul of the Rotoras, Vanessa (babysmurf on i-club) is running them, she drives HARD on the track, and she is happy with them.

[AtomicLabMonkey]

Originally Posted by sperry

And if I go for some new pads, what do you recommend? Hawks? EBC Greens?

My personal experience with Hawk HPS-Plus on my front brakes was less than stellar, so I won't be buying those again. I could still fade them on an autocross course, they made a ton of noise, and spread Evil Toxic Dust(tm) everywhere. Of course, this was on a nose-heavy Mustang with too much front brake bias (at the time), so take that with a few thousand grains of salt, your mileage may vary, yada yada, etc. etc. Since I loaded in the PBR compound that comes with the PBR calipers I haven't had any problems, they're just about perfect for autocross.

[ArthurS]

I have heard a lot of great things about the Carbo-Techs that SubyDude sells. Check those out also.

[Dean]

If you upgrade your front pads without doing your rears, you are messing with your bias... Won't matter on the street, but will at the track/autoX.

I like the Porterfield R4s on my A4 better than the HPpluses... The EBC Greens are working well on the WRX, but they do appear to be wearing quickly They may be ideal for autocross. I have a set of reds that will go in next in the front. I love all the data and options I have for the Stealth Wilwoods. I have at least 8 compound choices from Wilwood that are fully documented etc., as well as many other companies making pads for them. The Js are expensive but incredible. The Es are pretty good...

Any pad that is working will make "dust"!!! If you are making them hot, it will be flaming hot dust. Get over it!!! A low dust pad probably has a lower cf and isn't stopping your car very well. The dust is actually metal, carbon, glue, resin, ceramic... hitting your wheels at up to 1000 degrees F at very high speed. The only way to minimize dust is to clean and wax your wheels regularly if you are really worried about it.

Pads that can handle high temps are harder, will wear out rotors faster, and may make noise! Just like you can't make a good autocross/track/snow/rain tire, you cannot make a no dust high friction long lasting non rotor wearing, quit brake pad.

Rotors wear out! Keep this in mind with any system you upgrade to.

Scott, my recommendation for now would be to get matching Axxis rears if you have a supply of fronts.

KC is running the Carbotech Panther+ Pads in front, but I don't know if they will hold up on the track.

[sperry]

Originally Posted by Dean

If you upgrade your front pads without doing your rears, you are messing with your bias... Won't matter on the street, but will at the track/autoX.

Scott, my recommendation for now would be to get matching Axxis rears if you have a supply of fronts.

If I wasnt' clear about it, I've always had the Axxis Ultimates on both the fronts and rears. I just wore the front's out faster than the rears. So the last time I put new Ultimates on the front, I left the existing Ultimates on the rear.

I ordered some more Ulitmates, but screwed up and ordered two sets for the front instead of one for the front and one for the rear. So now I've got a set on the front of the car with 50% left, and two sets in my garage, and a worn out set on the rear and no spares! That's why I'm trying to find someone that wants to give the Ultimates a go on their car, so I can order some EBC's for the front and rear.

[Dean]

Originally Posted by sperry

If I wasnt' clear about it, I've always had the Axxis Ultimates on both the fronts and rears. I just wore the front's out faster than the rears. So the last time I put new Ultimates on the front, I left the existing Ultimates on the rear.

No, I just don't read to good.

Don't know about other sources, but the EBCs were pretty cheap from TireRack. They were out of greens in Sparks a couple weeks back though.

If you like the Axxis, spare sets are always good to have. You really can't track them with much less than 1/2 to 1/4 pad anyway or they can't take the heat.

Oh yeah, I forgot to ask. Are you running the stock pad spacer dealies? These sometimes are good, and sometimes bad. sometimes they shield heat, sometimes they make the pedal softer as they and/or the goo between them gets hot.

[sperry]

Originally Posted by Dean

No, I just don't read to good.

Don't know about other sources, but the EBCs were pretty cheap from TireRack. They were out of greens in Sparks a couple weeks back though.

If you like the Axxis, spare sets are always good to have. You really can't track them with much less than 1/2 to 1/4 pad anyway or they can't take the heat.

Oh yeah, I forgot to ask. Are you running the stock pad spacer dealies? These sometimes are good, and sometimes bad. sometimes they shield heat, sometimes they make the pedal softer as they and/or the goo between them gets hot.

Having never done a brake job myself, I'm not sure what's in there, I can only guess they're as OEM as possible. Wanna help me do my next brake job? I figure I'm competant enough to do it myself, but I've always wanted someone to walk me through it the 1st time just to make sure I don't miss something. Brakes are too important to "wing it", IMO. Plus, and tips on firiming up the pedal would be appreciated!

[AtomicLabMonkey]

Originally Posted by Dean

If you upgrade your front pads without doing your rears, you are messing with your bias... Won't matter on the street, but will at the track/autoX.

Here's the cure for that bias problem...

[Kevin M]

Originally Posted by AtomicLabMonkey

Here's the cure for that bias problem...

As long as not having ABS on a street driven car in Reno doesn't bother you. Otherwise I'd have one in my car too.

[MikeSTI]

F*** ABS just gets in the way