So i have two main issues that may be related. I am running stock calipers, Hawk DTC60 front pads, Hawk HP+ rear pads. All calipers float well (well-lubricated sliders w/ very high temp grease).

1. My rear pads are wearing pretty quickly... more quickly than the fronts! In addition, the outside pad is wearing faster than the inboard pad. Now the rear dust boots were crispy, and might've been causing piston binding / non-retraction; i just removed them to see if that could have caused brake drag.

Q: Any other thoughts for uneven and accelerated wear?

2. My ABS feels like it kicks in prematurely due to excessive rear bias. This would make me want to switch to a less aggressive rear pad to shift brake bias to the front. However, i'm already seeing high rear wear rates.

Q: Do you all usually run a less aggressive pad in the rear? If not, doesn't that cause the rear end to be unsettled and cause premature ABS activation from rear lockup?

EDIT: Here's a great thread on brake pad stagger, or not stagger.
https://www.rx8club.com/rx-8-racing-...r-bias-253256/

Thanks,
Matt

UPDATE 10/9

Ran DTC-60s all around instead of the DTC-60 front and HP+ rear stagger. Car feels amazing. I can brake deeper without ABS intervention. only one weekend so far so can't comment on longevity yet. But big thanks to the feedback from those in this thread - the brakes feel amazing now!

One theory is that the high initial bite of the HP+ pads caused them to create a strong rearward bias, especially at the beginning of the braking zone. This also led to high rear brake temperatures, and the HP+ is not rated for very high temperatures, accelerating rear pad wear. Now, with the pad compounds in happy harmony, my brake bias is good and i expect to see increased pad life.

I also lubricated the pistons and lubricated the caliper guides, so brake wear should be pretty good going forward.

 

I didn't think the hp+ would be a good race pad , especially when paired with a proper race pad like the dtc 60 . It may have the friction coefficient you want but will overheat well before the dtc60s will.

 

That could be what's happening. I am just worried if i go to DTC60 in the rear, i'll have even more rear bias...

maybe if my rear pads aren't dragging, they won't bite as early? haha.

 

Hawk talk about using the dtc70/dtc60 combo for this kind of application.
I have tried the DTC30 on rear with DTC 60 up front but the 30s still overheated . This was with wilwood calipers that were too small on the front though so ...not a good test.

 

DTC30 was originally a dirt track pad and now I think they use it or a variation for street/light track duty too.

HP+ are dirt, they're old technology from 20 yrs ago, dump that crap

You need at least HT10 with a DTC60 front. Dannobre has a ton of track pad experience with his 500+hp track REW-RX8. I'm sure he'll weigh in soon.

Scratch DTC50 for the rear, too high mu


.

 

Uneven wear with OE calipers can be the sliding pin hardware, you might R&R those parts as heat and track duty are hard on them, but clean and properly grease them at a minimum

 

You can't just go by this, but it still serves as a basic reference

 

I've run DTC60 front and rear and DTC60 front and HT10 rear

Didn't notice a huge difference between the 2 of them

I find usually that the rears last about twice the fronts....

Never noticed a bias problem...

The rear pads normally wear evenly inside/outside...so I would expect you have something sticking and not working as it should

And the HP+...they melt off when hot like butter.

I would try the DTC 60 front and rear and see how they feel

 

Thanks for the feedback, everyone. Hawk DTC60s for the rear are on the way. I'll double check to make sure the calipers are sliding well.

 

"Rotary engines are dirt, they're old technology from 60 yrs ago, dump that crap."


.

 

The Black are just as old, but superior performance and wear wise. Thanks for sharing your lack of experience though

 

You missed the point. No surprise given your reputation.
Thanks for sharing your lack of reading comprehension.

 

I had the same issue, calipers needed a rebuild.

 

reading comprehension or just poor communication on your part in the first place? You're a fine one to talk but feel free to believe whatever you want.



.



.

 

Do you believe it was the caliper guides/sliders, the piston itself sticking/binding, or both?

These calipers are only a few years old, but I guess it may already be time for a refresh...

 

if you take the pads out and mount the caliper you can see how easily it slides back and forth

Watch out for calipers rebuilt with plastic/phenolic pistons

 

You can even get then in racy red now

https://www.summitracing.com/parts/pwr-s2992

 

Yes the slide pins were corroded on the inside and one was getting stuck.

 

https://www.permatex.com/products/lu...rts-lubricant/

 

My favorite 😎 Purple lube 😉

 

Data point: HPS pads with maybe 10 track days on them. Can't get much more even wear than that. 75k miles on original calipers and hardware. My car doesn't see snow or salt and little rain, which makes a difference.

 

You.must have a track with very little braking....or else you just don't use them 😎

Thats about one track day wear when I tried them...and they were greasy as hell when they started smoking

 

Therein lies the secret of going fast with a low horsepower car ...

 

I use that on some of my brake parts, but I found it swelled the rubber bushings on the front slide pins, which caused my front calipers to sieze. I have used Sil-Glide on the pins since then with success. It is only rated to 500F, but those pins don't get anywhere near that hot. Most importantly, it is rubber safe.

 

Perhaps you used too much then. The boot isn't on there to fill up with grease. It's only to keep dirt and water out. If the pin is greased with the proper amount there won't be a bunch of excess to contact the boot.

I actually use a similar product made by a different manufacturer, but couldn't remember the company name