Pads for ST-40 calipers. What do you like and who do you get them from?

[ShadowBolt]

Dan and I run the R4, not the R4-E. I've been running it for a very long time and like it enough that I haven't tried any of the newer compounds. I have no data to compare it to anything else...

Richard P.

Thanks Richard. I hope I like the R4. The price of the PFC's are crazy when you look at them next to the Porterfields.


JJ

[marshall_mosty]

So what is the proper process for rotors if you switch pad compounds? Especially for floating rotors with slots... I'm not really interested in buying new rings to just change pad compounds.

[ShadowBolt]

So what is the proper process for rotors if you switch pad compounds? Especially for floating rotors with slots... I'm not really interested in buying new rings to just change pad compounds.

I've never had an issue as long as I was going from one race pad to another. When I used to drive my C6 to the track and change pads to race pads then change back to street pads I did have issues because the street pad could not knock off the transfer layer from the harder race pad. After a few days it would be okay.

JJ

[Suck fumes]

At the very least Go over the rotor with a buffer pad on a wiz wheel air tool really well and or resurface them. I know first hand going from a hawk to a Carobotech pad does not mix well! The car wouldn't stop worth a flip.

[BryanL]

At the very least Go over the rotor with a buffer pad on a wiz wheel air tool really well and or resurface them. I know first hand going from a hawk to a Carobotech pad does not mix well! The car wouldn't stop worth a flip.

I'm going to try Carbotechs in the rear instead of Azone golds. Rotors are fine but I don't like having them resurfaced after trying that and having them crack. What do I need to do to clean up the rotor? I'm not sure what kind of buffer pad you mean or a wiz wheel. Obviusly not the kind of buffer pad for detailing a car's paint. Any cleaners, scoth brite, emory cloth type of stuff to use to clean up the surface?

Do I need to do this when running the same carbotech compound on a used rotor?

[BlueFirePony]

I'm going to try Carbotechs in the rear instead of Azone golds. Rotors are fine but I don't like having them resurfaced after trying that and having them crack. What do I need to do to clean up the rotor? I'm not sure what kind of buffer pad you mean or a wiz wheel. Obviusly not the kind of buffer pad for detailing a car's paint. Any cleaners, scoth brite, emory cloth type of stuff to use to clean up the surface?

Do I need to do this when running the same carbotech compound on a used rotor?

If they cracked on resurfacing they were either resurfaced wrong or they maybe were gonna crack soon anyway. Check the rotor thickness and condition before handing them off and you should be comfortable having them resurfaced.
Cleaning the rotor is never a bad thing - if your pad requires bedding it's better to do with a clean rotor than a crapped up one. It really takes very little time.

You want all the spent pad material and any other crap off the rotor regardless of whether it is same pad material or not.
What I do:
A variable RPM tool like a circular buffer (not orbital, unless you want to chase it around) or sander makes it quick and easy using a gritty pad > 200 < 1500 - say 600 - it really depends how much crap is built up. I've seen people approach this like prepping a car for clear...using 1000grit followed by 1500 grit. Hmmm...I usually use more course.
If you do it without power, use a block...don't use your fingers.
You want a relatively low speed or you just might glaze the crap on instead of cleaning it off - start low and even and if it can handle more speed, pick it up. Should go quickly.
Just make sure you don't dig an edge and groove/gouge -have the rotor clamped flat so you can work it evenly. After I am done and it looks clean I dust and rub talcum powder onto the surface and take the wheel to it one last time to check for high spots and cracks. Then wipe with mildly soapy (like 4 drops/ pint) water and dry or use +90% isopropyl alcohol
My rotors have never failed me....yet. :/

[ShadowBolt]

FYI, Stoptech says when you can to use used rotors with new pads and used pads when changing to new rotors.

JJ

[Suck fumes]

I use an air grinder but put a scotch brite wheel on it instead of the grinder wheel.

This tool:
http://www.zorotools.com/g/00069620/...FQ_l7AodzCIAIA

[BlueFirePony]

So what is the proper process for rotors if you switch pad compounds? Especially for floating rotors with slots... I'm not really interested in buying new rings to just change pad compounds.

In short, if you are going to a pad with a significantly different operating range, material or bite you will want to resurface your rotors at a minimum and make sure your rotor's operating range (factoring in the resurfacing) matches the pad's. If you are going to an almost similar pad, then clean, scuff and check for wear, resurface if needed.

In long.....
When you change pads, make your rotor surface as much like new as you can.
A clean hard surface with directional edges (if you have slots, cross drilled or even partial drill) meets brand new consumable gritty surface. Look for high spots on your rotors, any cracks.

Also, if the pad and rotor temp range changes you may need to adjust how you cool the brakes and how you brake to take advantage of the pads/rotor behavior. Combinations of pads, calipers and rotors can create totally different behaviors.

If you go with the R4s they can operate with good bite from 400F or so to 1000F. Other pads need to be kept cool and some like to run hot. Where do your rotors run the best and how long do they take to cool/heat?

The APF02s I ran had better bite through their entire range than any other brake pad I tried (spec'd at .6 coeff of friction all things considered equal) but really grabbed in a range of about 575-850F. They also required less cooling to keep the bite higher but also cost twice what the R4s do. I ran several different sets of rotors (mostly slotted, some cross-drilled) most could not keep up with the pads and warped or cracked quickly. Changing the way I ducted the brake system could have helped. The DBA4000 (and then the 5000) were the only ones that could mate up with the APR pads. I raced almost exclusively on DBA and APR (some Mintex). I did a lot of trial and error in TT and DE sessions (probably over $3k in products).

When I was at a track (ECR) that lent itself to me being very aggressive coming off my brakes the pads needed to release fast so I used a specific pad that had great initial bite and came off the rotor quick - that's not just the pistons in your caliper..that's the behavior of your rotors and pads as well. Most pads did not release as fast as the APRs or the Mintex.

With the loose-is-fast setup I often needed to temper my release and some pads would overheat. A set of Mintex F4R (similar to the APF02) had a wider operating range (similar IIRC to the Porterfield R4) and had great initial bite and very consistent through braking, and required less cooling...and about twice the cost - $280-300).

[AI#97]

Glenn, for the non-abs Camaro setup like Misty has, we prefer the PFC01's (now the PFC 11) but there is a lot of initial bite. We tried a set of 06's and you can hammer the hell out of them as there is less initial bite and they modulate VERY nicely. We ran them for a weekend at Hallett and they barely show wear. Misty prefer's the 01's and we keep these 06's as spares, along with a ton of Hawk DTC-70's from a former life.

I think you would be happy with the 06 or the DTC-70. The 70 is probably pretty close to an 06 but a LOT cheaper....however, I personally can't stand Hawks and find I can overheat them pretty easily.

One thing you need to keep in mind is the stoptech rotors are MUCH more efficient at cooling than the factory stuff you have been running so don't be afraid of a pad that works in the higher heat ranges. If you are a hard charger under braking or are looking to catch up to the trophy girls, you are going to need a brake pad that can take the abuse and not fade toward the end of the race.

Misty said she might cut you a deal on these lightly used 06's if you are interested in trying them.