Brake pads for heavy turds

[CP]

Hi folks I need some input on track brake pads for 2 ton street cars. I’ve been using Hawk Blues on my Spec Miata for a decade and am more than happy with the bite and release characteristics of that pad after trying many other options. I like “tried and true.” Worst pad I’ve used for my driving style in the Miata was Carbotech. Their “easy modulation” didn’t work for me at all. I can modulate the Blues just fine.

That said, the 18yo Volvo wagon that I plan to run with COM weighs 1700# more than my race car and has factory 4-piston Brembos on every corner. I’m looking for feedback on track-only pads for a 2+ ton vehicle. Don’t care about cold/street performance, as I’ll be swapping pads/rotors for track days and trailering the car to events. Thanks for reading!

PS: I could use some advice on tires as well. I love the Toyo RR for racing but think a 200tw tire on a heavy street car (with coilovers, bushings and chassis braces) is a better option.

[beatus]

Woot, future sweedish cup champ right here. Looking forward to seeing it.

For brake pads, the important information is how much temperature you're going to be putting into the pads first IMHO. How big are the rotors on the car and what's the weight (sounds like 3500-4000)? Some small amount of brake ducting should go a long way to help for practice sessions.

I'd likely start with something like a dtc-60, as in my experience they hold up to the temperature well (hawk's chart state they operate well for a lot longer than the blues with temperature, so lines up with my experience). Blues basically fall off at 900-1000f, dtc-60 are good until 1400-1500. They also have similar friction as the blues, slightly higher. For what it's worth, they worked well on my saabaru with 13" rotors, wilwoods and a race weight of ~3250. My temp gun said I was getting things up to around 1300 and the heat paint on my rotors agreed (550c to 650c was the area, likely near the 650c paint as it was starting to change). There are other brands that will fill the same role as a dtc-60, but again the important thing IMHO is going to be temp tolerance with a car that heavy.

As for tires, I think it depends on the class and goals but for 200 treadwears the TLDR is something like:
- a052 is the outright fastest - Likes some `stretch` on a rim to be at their fastest (255 on 10" rim for example, a slight stretch). Sensitive to heat.
- RT660 - 2nd/3rd fastest? Less heat sensitive and doesn't care as much about a stretch (can mount a too wide tire on a rim and still get very close to maximum performance from the tire. Much stiffer sidewalls). IMHO these are the new re71r, similar tread (a little worse in the wet).
- naankang CR1 (or CRS now) - 2nd/3rd fastest? Haven't driven these myself but folks have said they have great grip in a slide or with some slip angle.

None of those are going to last all that long, though the rt660 should be dramatically more durable than the other two.

If you're not looking to be ultra competitive in a class, you could slot in a more value oriented 200 tread wear that will last a lot longer. RS4, rt-615+, the kuhmos, etc.

GRM has a great chart that breaks things down better than I can. It's not the end all, be all but it's very handy for figuring out which tires to try. https://grassrootsmotorsports.com/artic ... ers-guide/

[joncowen]

I agree with everything Brandon said. The Hawk DTC60 is also one of the cheaper options, so it won't be as painful to experiment. I'll add that the A052 requires lots of camber, and will get chewed up FAST without it. I'm told the Nankang CR1 is similar, but they are definitely a lot stiffer, heavier and not as fast, in my experience.
Lots of people love the Raybestos ST43 pads. I've never had them on a car that heavy though. And they may be tough to find.
The Hawk DTC70 is a bit more aggressive than the 60, but won't last as long. The website suggests it's for heavier cars. I tested the 60 and 70 back to back recently on my 3250lb E36 M3. The 70 definitely bit harder, but it was more difficult to keep the car out of the ABS. Very slightly too much initial bite for me, but not crazy. I was more consistent with the 60.

[beatus]

Agree with jon on the dtc-70s, I found them to be very difficult modulate because they'd just go right into abs. Maybe if I had more tire (245/40/17 rt660s was what i was running) and needed the extra bite/friction they'd be useful. I'll also echo the wear - they did not last long at all.

I did try gloc r12/10 after the dtc-70s and found they could not handle the temperatures I was reaching. Ended up back on dtc-60s after trying both of these pads last year.

[CP]

Thanks guys.

The car: V70R, 4000# with standard Brembo calipers so pads should be easy to source. Rotors are around 13”. I’ve got vents in the FBC and will look into running some short brake hoses but I don’t want to spend hours and hours getting the car prepped for laps. As it stands now, I’ll be swapping rotors and pads. Some of you may remember the black/grey two-tone Galant VR4 that I can with COM 15yrs ago. It used to take me several nights to get that commuter car ready for events and I’m not looking to repeat that.

For tires: I’m looking for something that won’t chunk after a few hot laps but weight may be against me in this case. I don’t care about lap times and would prefer durability but I’m not sure that exists in the 200tw range. I can use my street tires (PS4S) in the wet so tread pattern isn’t a concern for the dry tires. I’d go with slicks but really don’t want to be cornering that fast in a street car with no safety gear around me.

My intent: I’m just looking for track time close to home. I have no interest in time trials right now so my plan is to run Saturdays at Palmer and not push the car, as it’s my daily. I just want to get back on track after 2 seasons off from racing. Financially, this is going to cost about 25% of what it would take to get my SM ready to race again. And quite frankly, too many spoiled rich kids are getting into racing now and don’t mind wadding up multiple competitors to gain a position because Daddy will pay for it. Covid presented a good opportunity to take a break.

[CP]

Any experience with the Kumho V730 (235/45/17)?

[beatus]

For tires: I’m looking for something that won’t chunk after a few hot laps but weight may be against me in this case. I don’t care about lap times and would prefer durability but I’m not sure that exists in the 200tw range. I can use my street tires (PS4S) in the wet so tread pattern isn’t a concern for the dry tires. I’d go with slicks but really don’t want to be cornering that fast in a street car with no safety gear around me.

Any modern 200 treadwear shouldn't chunk, but given what you're looking for you definitely want an endurance 200 treadwear. You can buy pretty much whatever you want in 200 treadwear, the endurance tires will last longer than just about any other tire out there (maybe some "hard" compound slicks will last longer? The federal hard compound comes to mind here). The TT / max pace tires are as fast or faster than many 100 tread wear semi-slicks of yesteryear.
- RS4
- New conti/hoosiers: "extreme contact force"
- falken rt615+
- Nitto NT01 if you want a slight bit more pace, also wear well (but worse than the above tires listed). Lots of folks swear by them in the club and they don't heat cycle out.

All of the above won't be horrible in a TT, but will be off pace for the points they cost (probably a few seconds at Palmer, as a reference). I've run the RS4 at a lemons event and it lasted the whole weekend in with barely any wear and extremely consistent performance. Granted it was a 2800lb car or so, not 4000lb, but guys with the big boats also run them. My pick would be the RS4, people have a ton of laps on them and they wear like iron. Contis if you feel like trying something new that few have run yet (they came out in very limited supply end of last year).

Any experience with the Kumho V730 (235/45/17)?

No, but I hear they're competent enough. I'm sure somebody in the club has tried them and I've seen them at HPDEs.

4000# with standard Brembo calipers so pads should be easy to source. Rotors are around 13”

That's a heavy car for that sized rotor. As long as you go into the practice 20 or 25m sessions with an attitude that you may need to back off for a brake cool down lap mid session I think you'll be fine. It's certainly a big change from a spec miata class car that's super nice on consumables.

[joncowen]

From what I read, I think I'd still pick the Falken RT660. It's cheap. It's quick. It's fun to drive. It's somewhat durable, assuming your suspension geometry isn't crap. And, if it's only driven at the track on Saturday as described, I'd bet it will last a good number of days. I personally would have much more fun in a 20 minute session on the 660 vs the slower endurance tires.

I've heard some good things about the V730, but not enough to comment.

[beatus]

Yeah, I do have to agree with Jon again. RT660s are a good sweet spot, I personally got around 12 days out of my practice set this year and they're still not quite corded (but are heat cycled out and a bit slower). I also run them in the TT and had good results with them.

Just keep in mind they run super wide.

[paultg]

Cy, great to hear you will be back attending events. The info above pretty much covers it.
I agree with the RS4, RT660, or NT01 as your best options, lap times in that order too (slow to faster).
I think with only doing Saturday events it's your pick on how fast you want to go vs. risk of them wearing out vs. cost.
Tire life will really depend on the car suspension.
It might make sense to start with the RT660; if a 2nd set is needed due to wear it's probably similar in cost still to a single set of NT01s.

I run the NT01s on my MX5 (2010 NC), do both days, and flip on the rims mid season to extend life.
I probably toss them too early to be honest as I always want to start on a fresh set the following season.
They are a really fun tire to track on. You can slide them around without concern; and they just stay consistent until they cord.
I don't have any direct experience running the other options.

[CP]

NT01 is where I think I’m headed. 235/40/17 (stock size is 235/45/17 but unavailable from Nitto). I ran a set of these about 9 years ago on my Miata and I remember them being pretty durable, like the Toyo RR that I’ve been running ever since. I get a good 30+ heat cycles from the Toyos and they don’t fall off much. I’m not a fan of Hoosiers. They heat cycle out way too soon and take too long to come up to temp (I pass lots of guys on Hoohoos during race starts when we get to that first corner, like NASCAR 1/2 at NHMS ;^)

I’m trying hard to keep this a comfortable street car. It’s camber challenged and I don’t want to add camber plates. It will be corner balanced in the spring. I’m walking a fine line here because I’ve got a race car in my garage but I’m just not having fun racing right now, and that’s really what it’s all about. I think this heavy grocery getter will be a hoot on track if I can get it to slow down and corner reasonably well. Should I keep the booster seat in the back?

[paultg]

Is there a reason you aren’t just running the spec Miata with us?
Could run it in touring or super and just a 205 Nitto last you all season for sure.
Lots of comparable cars and drivers to have fun with too.

[CalypsoBean]

I realize I am late to this conversation, but I ran Nitto NT01 on my 3,750 lbs Cadillac for several years and they did great. I tried several 200 treadwear tires and got more chunking than I would have liked, but never had that problem with the Nittos. They wear well.

I echo the opinion of bringing your Miata instead, tho. As much as I am a fan of being different at the track, the V70R does not have a good reputation for reliability when abused, particularly the AWD system. It seems like a lot of effort to turn a GT car into a track car when you've already got a track car waiting.

[CP]

The Miata will require a significant investment to get it track ready again including multiple sets of tires, new belts, some fender/suspension damage repair and another alignment. When all that is completed (next winter), I’ll weigh options for track time. The budget isn’t there this year.

I have acquired a set of titanium shims to place behind the front pads of the Volvo in hopes that they’ll help mitigate heat transfer to the fluid in the calipers.

[SquidInk]

I don't have a lot to offer other than I run DTC-60 year round on a 3300 lb GTI. No problems on track with single piston calipers.

I wasted a set of 255/35-18 PS4s in the dry once I started to push.

Not brake pad related, but the turbo really liked unleaded race gas- it was quicker and intercooler heat soak didn't ruin the fun as much after 2 hot laps.

You need a Tom Walkinshaw Racing T-shirt!