Dual-use brakes: Working fast street pads hard vs. largely underusing track pads?

Nearly ordered a pair of GT3 front ducts for my 86 with the plan to use them with streetable track pads, but then I thought, what about pad break-in? These ducts are really just big scoops that pull air from under the car, there's no hole in the front air dam I can tape over to disable the cooling when trying to break in new pads. That would be asking for trouble with this kind of pad.

Considering the options eventually got me thinking that maybe I should consider a different approach to my goal, which is to put together a fairly cheap and low-maintenance brake setup that will perform decently on track and won't be too screechy or cold for street and autocross use. Two ways I could do this:

1. Use more aggressive streetable track pads like EBC Yellow / Blue / Orange with a more traditional brake vent system that can be blocked for break-in. Definitely won't overheat - the vents are for extending rotor and pad life rather than preventing brake fade with this setup - but will be more noisy and dusty on the street, more grabby and temperature-dependent in autocross, and will still eat rotors faster.  Probably the more expensive option. I went this route with the AE92 and it's been tolerable on the street and good on the track but just adds challenges to autocross...but then that car doesn't have ABS.

2. Use less aggressive and cheaper performance street pads that can survive some track use and keep temperatures under control with the always-on brake cooling, should break in at lower temperatures so no need to disable cooling or make room for brake vent inlets. This setup will be easier on rotors, nicer on the street and more controllable in autocross, but still has the potential to get melty on track and the pads will likely disappear faster. Probably the cheaper option in the long term.

Thoughts?

You've correctly analyzed the pros/cons.  I've done both, and now I keep a separate set of pads for the track. 

I'll throw the Powerstop Track Pads in the ring as a good option. I've run them on my Legacy but my friend is also running them on his '15 BRZ. They work well from cold so are a great choice for Autocross but they can definitely handle the track. We were on a short track a few weeks ago (Grand Bend Modified course) which was from memory just over a minute a lap with three hard braking zones every lap and little cool down between. These pads took it without any fade or issues, the only other thing changed in the system was fresh ATE Typ200 earlier in the year. The pads do dust as expected but squealing hasn't been a problem. The scoops will only help but I don't think they would prevent proper bedding in at all.

I personally run the Track Day Spec version on my E28, they are better on track but need heat in them to work so aren't great for Autocross. The pads are very affordable through Rockauto, don't forget the 5% discount code on this site. I won't call them cheap because they actually work very well at about half the price of a comparable Hawk HP+.

I haven't found a great answer to this question. I really really really like good brakes on track, so I'd recommend two different sets of pads. You need to pull the wheels off and inspect the brakes before every event, anyway. 

I guess the other question to ask is what sort of tire are you running on track/autocross? If you are on 9" wide wheels with the stickiest 245 tires than a true track pad is going to be the answer. The BRZ I mentioned was on 17 x 8 with 225 RS4's just as a data point and I drove it for my last session so it was first hand experience.

I think you're overestimating the effect the cooling ducts have. I really doubt they would affect bedding, but even if you can't quite get it done on the street one session on track will do it for sure. And that's for track pads, street pads will bed no problem.

Personally I can't stand noisy brakes on the street so I went with porterfield r4s which are awesome on the street and surprisingly capable on track. I ran them just past their happy heat range...but I was stopping from 130 on the mid Ohio back straight, and pushing that braking zone as much as I could. They never caused any safety issues and never really faded but looking at the pads afterwards it was clear they had gotten a little bit too hot. But if you have a little bit better brake setup and a little bit more cooling and aren't quite as aggressive (or the track you're driving isn't as demanding) they'd be fine and probably are what I'd pick for a multipurpose pad. As mentioned they wear a bit quickly but last I checked they were the cheapest option in that performance category and are dead silent on the street and not too awfully dusty.

In my case I decided it was time to step up to track pads but as mentioned I hate noise on the street so I got a set of compatible track pads and swap them out and live with the noise driving to and from the track.

It's pretty easy to swap pads.  I'm running the GT3 air scoops held on with zip ties for track duty.  When I get home I swap back to street pads and snip the zip ties to keep the scoops with the track pads.  Dual duty pads are like all season tires.  Just, no.

adam525i said:

I guess the other question to ask is what sort of tire are you running on track/autocross? If you are on 9" wide wheels with the stickiest 245 tires than a true track pad is going to be the answer. The BRZ I mentioned was on 17 x 8 with 225 RS4's just as a data point and I drove it for my last session so it was first hand experience.

I'll be running 225 to 245 wide tires of longer-wearing 200TW compound like the RS4s. The hardest braking the car is likely to see in the near future would be approaching Moss corner at Mosport.

Given the importance of bedding in as I understand it, and getting a layer of compatible friction material on the rotor (or drum), I guess I'm still puzzled they it's okay to just swap pads back and forth between different compounds... Anybody able to shed some light on that?

Compatible compounds is the key. I'm going to be honest I'm not 100% sure on the science behind it but generally compounds made by the same manufacturer are similar enough that they can be used interchangeably with little to no bedding. Some pads from different manufacturers are compatible as well.

In my case it's porterfield R4 (track) and R4S (street). The first time I ran the R4 they needed a thorough bedding (which seemed to not really be complete until about the second track session) but since then swapping back to the street pads they feel normal about three stops in and swapping to the track pads they feel normal after a lap or two on track.

I used to run the PFC97 as a do-everything pad. And they did. No matter what, the car would stop. 
 

But when run cold on the street, I'd use up two sets of rotors per set of pads. It just not worth trying to do everything with one compound. 

I've been happy with Hawk HP plus. Had R4s before, I like the Hawks more.

GameboyRMH said:

adam525i said:

I guess the other question to ask is what sort of tire are you running on track/autocross? If you are on 9" wide wheels with the stickiest 245 tires than a true track pad is going to be the answer. The BRZ I mentioned was on 17 x 8 with 225 RS4's just as a data point and I drove it for my last session so it was first hand experience.

I'll be running 225 to 245 wide tires of longer-wearing 200TW compound like the RS4s. The hardest braking the car is likely to see in the near future would be approaching Moss corner at Mosport.

I guess the next question is, will you be flat through turn 4 or not? My instructor over the past weekend there mentioned he felt like he was on the edge of what the stock brakes could handle on his 2013 BRZ by the end of a twenty minute session going into 5 but that was at a very high pace pushing every lap with fresh 225 RT660 on the car in the instructor/solo group with approximately 450 lbs of driver/passenger in it. I believe he was running one of the less aggressive Hawk DTC pads so he was probably at the limit of heat that the system could shed and those deflectors would likely help. Keep in mind this is full blown, all out pace every lap in our 30+ degree heat over that weekend. 

The Track Day Spec won't let you down but like a true track pad at an autocross the first hard braking zone won't feel as good as the second. Looks like they're about $200 CAD front and rear as a data point at Rockauto (-5% with the coupon). You'll save $20 going down to the track day and I think they would hold up as well unless you are at an advanced level of driving on track and really pushing the brakes, they are decent to daily though and great for autocross. 

Any plans for TMP? I feel like it is just as hard or worse than Mosport with the braking zones into 1 and then again into 2/3 followed by a shorter lap. Maybe we'll run into each other at some point at an event, my car will likely stand out a bit more so if you see a red euro E28 come up and say hi.

Agree with the guys that say street pad for street and competition pads for competition.

I run somewhere in between on my street sports cars as I sometimes drive them aggressively (EBC Redstuff on one, R4-S on the other) but have no delusions about them ever being adequate for actual track use.

In the old days when asbestos was still used, I ran Ferodo DS-11 on the track but it would have been a horrid street pad - little braking until you got them hot. I switched to R4 when the DS11 became unavailable and found they were much more effective when not hot, but whether one could use them for dual street/competition I rather doubt.

I'll eventually work up to staying flat through turn 4, may make some trips to TMP as well, which does have some pretty heavy braking zones now that you mention it, although they're not nearly as scary as Moss corner But I won't be doing any track days until after I finish getting all the oil control/cooling and brake mods done on the car, which will probably be next year.

I don't think swapping pads for this car makes sense, I don't have a commute now so the car only gets driven on the street a couple times a week at most, and will be parked all winter. For that little street driving I'd sooner run track pads full-time than switch pads back and forth. But having gone for this sort of overkill option before I think I'd like to try approaching the problem from the other side this time. I think I'll try the Powerstop Track pads with the GT3 ducts and move up from there if I get brake fade on track. Probably try TMP first since they have a lot more runoff room...

I've used the Track Day PST pads on the street and in autocross now so I can start on a review:

So far if you'd swapped my old Akebono street pads for these without telling me, the only hint I would have that something had changed would be a bit of squeaking when coming to a complete stop when the pads are stone-cold, or perhaps literally ice-cold - I haven't driven the car in temperatures much above 10C yet. They're just like ordinary street pads for street use. I heard these are very dusty pads so I put some Armor-All protectant on my summer wheels before fitting them up. In light use they don't seem to be dusting more than ordinary street pads so far, but I picked up a lot of road spray on my longest drive on them so it's hard to tell.

Will probably have a track use review in the late summer/fall.

I've always run track pads and street pads.  I don't want to deal with noise and dust of track pads on the street and I want proper braking on the track

Additional note - manufacturers today usually opt for cheap pads that are adequate for driving to the store and back, and should probably be jettisoned at the first opportunity.  The hard choice ia always what to replace them with - dual purpose pad or semi-comp pad.

One exception to the  so-so pads in new cars was (surprisingly) in my old Lamborghini.  I suspect that disc brakes were new enough to them in 1968 that they just looked for what was the best pad available and went for Ferodo DS-11 (which I mentioned earlier in this thread). While very capable at the 'hot ' end of things, they suck when dead cold - every first lap at my local track in my old British race car I would slide the rear end of my car around the high speed hairpin in the gravel - every lap after that they were perfect and never faded.  That's OK for a race car but the first stop or two on a cold morning with something like a Lamborghini might have been a tad exciting, particularly if you pulled out of your driveway onto an autostrada and went to high speed mode. That first stop of the day would have been a tad exciting.

Pad choice has to depend on your particular circumstance.   A good all round street/high performance pad should be the first purchase when you get a new car.  Whether you need a strict competition pad depends on whether the sort of auto sport you participate in involves higher speeds for extended duration (like track lapping vs. Solo events).

Actual race pads do NOT stop well without heat in them.  Like you will poo a little when you drive on the highway for a few miles and then need to stop.

Not all pads that take heat well are made equal.  For a while, I was running the Hawk HP Superduty pads (similar to the HP+ compound) on the Jeep.  They absolutely sucked cold.  Not awful in the summer, but in the winter you had to be really mindful of them, as it would take a second or 2 of hard braking from full cold before they'd wake up.  The first bit was almost scary weak. 

Later on, I switched to Carbotech AX6s.  The Carbotechs dust a whole lot worse and they occasionally squeal slightly under very light braking (the Hawks were silent), but they stop well from cold (better than most parts store grade street pads) and with just a little heat in them, they stop incredibly well (at least as well as the Hawks did).  Based on how hard it was to get them hot enough for a proper bed in and the total lack of fade while attempting it, they seem to take heat even better than the Hawks. 

I'd absolutely suggest the AX6 for a dual purpose pad if you can live with the absolutely incredible amount of dust they produce (it cleans off very easily though). 

My solution on the Datsun (strictly track car since 1991) was to install oversize brakes (Z car) and just run a quality street pads. 

Still haven't taken them on track but I've done some more autocrosses and street driving, and I can confirm that these pads are dustier than a sad movie in a sandstorm now, moreso than EBC Yellows. If you want your wheels to look nice these pads are your worst enemy, the only time I've seen my wheels clean in the last few months was between cleaning them and driving the car. The dust does clean off easily though. I did use some armor-all wheel cleaner + protectant on the wheels when I put these pads on, so that may be a factor.

Also they are capable of minor squeaking at low speeds even in summer temperatures.

Keith Tanner said:

I used to run the PFC97 as a do-everything pad. And they did. No matter what, the car would stop. 
 

But when run cold on the street, I'd use up two sets of rotors per set of pads. It just not worth trying to do everything with one compound. 

Same experience as Keith with the 97's.

I think with regard to swapping pads and bedding, it's more about the street pad transfer layer not being incompatible with the track pads.  One session on the track will generally create enough heat to bed any pad, the prior transfer layer just needs to not be in the way.

Update after the first track day (at the FIRM): The good news is that the brakes performed well, good consistent performance. The only issue I noticed was a light scraping sound once the brakes got hot (this is called foreshadowing...)

The bad news: A lot of brake pad material transferred to the front discs:



And the rear discs were left completely FUBARed, grooved all to hell and there are signs of heat discoloration in some spots:



The front discs are clearing up with wear (these pics were taken after driving back to the hotel from the track) but the rears may be metal-on-metal at this point and certainly sound the part. I did notice the rears smoking when I came off the track even after a cooldown lap while the fronts were not. So I should consider adding a vent system to the rear as well.

I could step up to the Track Day Spec PSAs, I've seen a review from another driver who tried both on Laguna Seca, the PSTs melted but the PSAs have held up.

In reply to GameboyRMH :

I don't know 86s well but was the stability control partially on? If you are aggressively rotating the car this will cause the rears to overheat.

Also if the pads were thin that will also do it. I milked the rear pads on my formula car and I would actually get a soft pedal. Put fresh pads in and the problem was gone.