Casem1

I have searched and read all of the posts regarding street tires and pads but still wanted to start my own.

I thoroughly enjoy track days but I am starting a family and scaling back on expenses. That being said, I am still going to do HPDEs.

For cost reasons I am only going to use street tires. I have been using gForce KDs (treadwear of 220 i think) and they have been nice but they are not available anymore. I am looking at Dunlop Star Trac or something like that and they are rated quite highly. Anyway, whatever the stickiest street tire I can find is, I will use those. My brakes are stock calipers with stainless lines, DRM ducts, Motul bled after ever event. I have been using C5Z06 pads. They are predictable this time of year but fading was noticeable in July/August events.

Now to my question: Is there any real benefit to running more aggressive pads with the street tires? I will not use HP+ pads, and understand there is no benefit to HPS vs C5Z. I guess what pads I am wondering about are Wilwood E, PFC Z or even Wilwood H (in the TX summer track days). But, I want to know if there would really be any benefit. Added obstacle, I like my rotors lasting long also.

Whatta ya think?

Additional Q, would adding stainless caliper pistons make any difference?
i.e. less fade with C5Z pads?

Aardwolf

I used some Carbotech XP8's and had no fade and also used street tires. I had fade with ZO6 pads! The XP8's felt hard and didn't stop well as for the first mile or two of street driving, after that they were excellent. They would stop the car fine but I could tell they were cold. They seemed to me to have about the same bite as the ZO6 pad but handled my track use much better. I use street tires and just drive to the track for HPDE. I decided to leave them on for street driving as a test, which they past! I'm thinking of running XP10's all around this year, I've increased my HP. I'll still be on street tires though.

sperkins

Aardwolf and I pretty much have the exact same thing to say. I use XP8/XP10's as well. He's right about the fact that they didn't grip very well initially, but as they heated up they were much better. Maybe it's just me, but the initial bite now is much higher than with my C5Z pads. I also had fade with the C5Z pads, but not so bad with Carbotechs. I've run entire weekends with these pads and street tires with good results though I obviously didn't brake as hard as when I had sticky tires. The only negative side to the Carbotechs on the street is obviously the dust on the wheels and deposits on the rotors. Once I get them up to temperature though the rotors clear up just fine. The Z pads are pretty good, but ultimately it depends on just how hard you're planning on pushing it.

97coupechuck

What's wrong with HP+? I run them all the time for both DOT's and street tires, I recently tried out HPS on my C6 Z51 because the drilled rotors were cracking with HP+ but after running a HPDE in Hitchcock a couple of weekends ago, the HPS's still added to cracking (small) AND they didn't work well at all. Going back to HP+ with smooth rotors.

Casem1

My impression is that there are pads that last a lot longer and are easier on rotors. I actually read a few posts where people were very disappointed with them. Thats all i have to work with, what people post here. Maybe someday i can convince pad companies to donate all of there pads to me for a comparison test, but i doubt it

VetteDrmr

No direct experience with the HP+ pads, although I've got a set at home waiting their turn.

I've been using the PFC Z-rated pads for several years now, and they work great for autocross and DEs. Please note that when I'm running a DE I don't brake deep and hard to get those tenths, rather work the car in the corners and exiting.

Running Toyo RA-1s (which should be more grippy than whatever street tire you run), I've not had problems with pad fade nor fluid boiling. Pad taper does happen, but that happens regardless of the pad.

Dusting is maybe a bit more than OE, but not bad. Rotors will heat-check, but I ran 3 seasons (1-2 DEs per year) on a set of rotors.

Point is, if you're going to limit yourself to street tires, I think you'll find the PFC Zs to work well for you.

HTH, and have a good one,
Mike

Jason

I liked HP+ pads as good street/autox/track pads. They do dust, but that was always a trade off I was willing to make (and I powdercoated my wheels black).

Akcelr8 N VA

I'm sure you've thought of this but I'm going to say it anyway. Pads/rotors/tires are a system and have to work together. Don't get a pad that's too aggressive for the tire. You'll be into the ABS all the time trying to keep the tires from locking because the rotor/pad can outbrake the tire's traction limit. Or, if you don't have ABS, you may lock up the tires before getting full benefit of the pad. I too used PFZs when I ran street tires. They were a good compromise for track and street use.

Casem1

This is exactly what i am asking: can i really benefit with more pad with street tires? Or, should i try even harder to keep brakes cool with C5Z pads? (such as stainless pistons)

Aardwolf

For my deep braking driving style, I always want more pad and less fade. I did not like the HPS, PFC-Z, or ZO6 pads, with the Carbotechs I could brake at the 3 1/2 marker which made me happy. I'm sure my C4 isn't as fast as your car so decide based on your driving style. If I had your car I'd use even more pad and cooling.

0Todd TCE

Polymatrix H pads should be ruled out immediately for ANY street use. They are a dedicated track pad and will provide marginal value on the street as well as a lot of noise and dust. Much of that being rotor wear....

Polymatrix E compound would be 'streetable' but will result in a clear metallic and loud pad with moderate dusting levels. While ok to some others will find this pad too intrusive for a daily driver.

Akcelr8 N VA

In a word, No.

Two thoughts that may lead to a conclusion: 1) Performance (race) pads require heat to work well and can take higher temps before fade occurs but may easily "outbrake" tire traction with street tires. 2) Street pads don't require a lot of heat to work and may fade at track temps but won't as easily outbrake tire traction.

Going with option 1 means you won't be able to use the full capability of the pad and it may be harder to modulate your braking on the track as well as being "less than ideal" for the street. This leads me to suggest using a non-race pad (or at least a less aggressive track pad) to match street-tire traction limitations and provide as much brake cooling as possible to reduce pad fade. Your approach of stainless pistons as well as duct cooling, high temp fluid and stainless braided lines (for safety as well as reducing line expansion causing a spongy pedal) should provide you with the optimum braking package using street tires. The trick now is to find the pad that matches your street tire traction capabilities. One way that I've encountered is to identify how easy it is to get into the ABS under threshold braking. When matched correctly I can threshold brake without hitting the ABS However, as my tire traction is reduced, either by heat build up or too many heat cycles I find that I can get into the ABS well short of my turn-in point. My pads are braking better than my tires and more brake modulation is needed.

Wow, I didn't mean to write a book.... I hope this helps.
--Ralph

FasterIsBetter

Drilled rotors will crack under track use, no matter what pads you are using. I had this discussion with Wilwood this summer, and they say that drilled rotors should not be used for any racing application, even HPDE. The heat generated on the track simply causes the stress points created by drilling to crack. They recommend solid rotors or slotted only, no cross-drilling, for any track application, regardless of whether you are using racing pads or street pads.

Aardwolf

I was looking around at pads a few months ago, a lot were listed at 150° min. temp. That is really not much. It really wasn't a big deal to get them warmed up for the first mile. It's so easy to change pads that it really doesn't matter. I 100% think that you will vastly benefit going to more pad then the ZO6 pad with street tires.

MungoZ06

I broke down stock Z06 pads and (with cooling ducts) still put a lot of heat into HP+ pads using stock F1SC's. I found the Carbotech 10/8 combo to work OK, even with Nitto 555RII's which is about the most aggressive "street" tire (meaning you can drive it to the track). Kumho has a new 180 UTQG rated "XS" tire just out that has a thread something like the Falcon Azenis 615. Don't know anyone who has run them, tho good sizes for C5Z stock rims. ...

Z06Fix

Hawk HP+ have been my favorite street/autox pad.

I have run 3 compounds from carbotech and just didn't find them to be consistant. This most likely due to me being in and out of their heat range, but I needed something that worked everytime I went for the brakes. The hawks have done that for me nicely.

I will be using Wilwood H or Hawk DTC 70's for track use.

Rob Willis

This past summer I ran PFC01s with the stock Eagle F1 Supercars.

More pad then tire for sure, but it worked ok.

I ran a 1.23.00 at Putnam with this setup, which BY NO MEANs is fast, but is respectable.

However, it doesn't sound like the PFC01s are something you'd like.

avizandum

I run Carbotech 8/6 combo. I chose this combo after speaking with them at length.

DD, lotsa AutoX, occassional HPDE. Dunlop Direzzas in the front, Kumho XS in the rear.

I really like this combo - pads with tires. Definitely more analogue than the stock Z51 pads. Good cold bite and dealt with high heat. Cooked my OEM fluid before the pads lost bite. VERY rotor friendly. Just drag your brakes for AutoX and they're right there.

Very noisy and dirty though - gonna try to taper the leading edge this year.

Umrswimr

I don't see that there is a problem with running aggresive pads on street tires. The biggest advantage is the lack of fade which was a constant problem in Texas on C5Z pads. Yes, you'll have to be more careful as it'll get into ABS more quickly, but the benefit of not having the pedal go to the floor mid-session is worth it.

I change pads at the track- EBC Yellows.

elh0102

Well, you have a couple of seriously conflicting goals here, high torque performance, and long lasting rotors. As others have said, race pads will overpower street tires, which means you have to develop a more sensitive braking feel to stay out of ABS excessively. No big deal, just takes some experience with the pads. IMO, it is a much better option than dealing with premature fade with street pads. I think you would find the Carbotech XP 8 pads very capable, and relatively easy on rotors. The XP 8/6 combo might work very well for you. Most folks find HP+ pads unsuitable for hard track use; might be fine for autocross.