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Callsign_Vega 12-21-07 12:22 PM

Howard, correct me if I am wrong, but you still have the first gen initial brake kit that RB set out correct? You aren't seeing any of these large flaws that others have mentioned? Being in Iraq and having no access to the BBK in storage, I pretty much just need to know if I wasted thousands of dollars on this kit or if it is a decent kit and I just need to use non-RB pads.

Howard Coleman 12-21-07 01:01 PM

first off welcome back and thank you for your important service to our country.

i am fairly sure that my kit is the first of the first generation. if you note the very recent prior posts there may be a "rust ring" at the inner edge of the rotor on the first group that might bite into the pad at it's inner edge. in which case i would just space it out a tenth of an inch w a spacer.

my pad is properly aligned as i have no inner pad overhang. so i am getting all of the pad biting against the rotor... and yes, if i were to space it out another tenth or so i would get more leverage. maybe i will do that.

other than that first gen owners need to do a bit of filing on installation. it is easy and in a non structual area of the upright. i did post pictures a while ago on this thread. i would be happy to email them to you is you PM me your address.

i have run ET500s, ET700s and ET800s. i settled on the ET700s for the street and they work well. i wouldn't hesitate to run any of them on the street.

the track apparently is another matter. since the front pad is one of the most common pads there is a breadth of options available for tracking.

i will find my measurement sheet and post the details.

you will be in for a treat when you first step on the middle pedal as this system generates a lot of torque and thanks to the rear upgrade it is pretty well balanced. i am very happy w my first gens and certainly will have to deal w finding the right pad solution for the track.

hc

hyperion 12-21-07 03:51 PM


Originally Posted by 1st to 3rd (Post 7650957)
I will measure the caliper piston imprint on the pad backing plate as shown in the picture. Howard & Hyperion, could you do the same? I’d like to compare results.

Something I'll measure when I get back to my car in January. To be honest, it would be great if the top-to-bottom taper is caused by piston misalignment because that's something that can be easily fixed. Caliper flex, on the other hand...

-ch

GooRoo 12-31-07 12:26 PM


Originally Posted by hyperion (Post 7631675)
<snip>

There was some leading/trailing taper, and my recommendation to RB is that a larger piston stagger would help. (This is backed up by a noticeable temperature gradient across the backing plate.) But that's not too big of a deal. However, I am noticing a pronounced top-to-bottom taper on the outboard pads of the front calipers. I believe this is consistent with caliper flex. I would love to get some data from GooRoo or Damien on their pad wear to see if this is typical of track-driven cars with the 993TT or StopTech brakes. I should add, however, that this taper did not affect braking performance at all. I think you could run most of the season on a single set of pads.

<snip>

-ch

I did find a couple things on my pads with the 'new' (to me) 993TT front setup:

1) As compared to stock, I have alot less leading pad wear, so the pads last longer. I would say that I also still have some leading wear taper, particularly on the outboard side as you mentioned, even with 36mm leading and 44mm trailing pistons. However I swap the pads side to side a couple times during their life and am able to even this out and it really hasn't been an issue for me. Also of note is that I only used 2 sets of front pads for the entire 2007 season. For 2006 I burned up a set every single weekend.

2) I do not have much radial (I think that's what you mean by top to bottom?) taper at all in the front. I have never measured this because I never noticed any, so I don't have any numbers for you. I have gotten taper in the rear when I've been very aggressive on the pedal and when I installed the pads wrong one time. :D

Couple other notes: (some of this repeated from elsewhere)

1) I will say that when Damian's car was not braking well he did have pronounced radial taper. Last year when we were doing our testing we could literally see the caliper opening up when we tried to replicate what was happening on track. This was before he had the Stoptech setup, and to troubleshoot he first replaced the 993TT calipers and the same thing occurred. At that point he went with the Stoptech setup to see if that fixed it. While the Stoptech calipers were way better with regard to flex, we could still see some, and the car still wasn't braking well. In the end what fixed it was getting a dual pressure gauge so that we could see actual brake line pressures. Once the numbers were known we could see that the bias was off, and he replaced the rear master cylinder to lower the pressure. On-track braking feel went up, wear went down, radial wear was gone (along with the bending of backing plates) and input and line pressures were down as well. The brakes were much more consistent in the 40 minute races and the temps were way down on all 4 corners.

2) Of course in the middle there, I bought the 993TT brakes and put them on my car and everything worked great, so we knew the calipers and rotors themselves weren't the issue.

3) Damian's Stoptech setup has custom 36/42 piston sizes and 13"x1.25" rotors

4) We both have really large front ducting setups pulling cooling air from the nose of the car

cabaynes 12-31-07 01:18 PM

Nice post. What are you running on the rear? And also what type of pads?

hyperion 12-31-07 04:11 PM

Thanks, Andrew. Great post.

StopTech put a lot of design work into limiting flex on their calipers. I talked to their development engineer a few years ago and he had quite a bit to say about it. One of the things he highlighted was that the 993TT (Red Lobster) calipers are some of the worst when it comes to flex. His impression was that Porsche made them big for show. (The newer monobloc calipers are supposedly much better.) An Alcon engineer had similar thoughts on just about all production calipers.

But anyway, as far as leading taper goes I think what I've seen so far is acceptable. I think I can get at least 4-6 track days out of a set of pads--and this is with 3100+ lbs and 430 RWHP.

The radial taper is still a bummer. I will measure the location of the pistons, but I'm pretty sure it's due to flex. Perhaps pad switching will address the issue on the track--we shall see.

But all of this aside, I think there's a point that RB has made to me that's worth repeating: they are not trying to design the ultimate brake kit for track use. They're trying to provide a good value performance ratio. If--and that's still and if--I can get the kinks worked out, I think this kit is capable of running consistently into the high 1:30's at Laguna Seca without ducting. That's faster than a lot of very expensive cars, including a brand new GT3 RS driven by Speed GT champion Johannes van Overbeek (who I paced for a lap at Laguna in December. He's quick.)

Not bad. But like I said, I have to get all the kinks out first.

-ch

GooRoo 01-01-08 01:05 PM


Originally Posted by stokedxiv (Post 7681537)
Nice post. What are you running on the rear? And also what type of pads?

Both Damian and I are running the RB rear kit with HT-10 pads.

GooRoo 01-01-08 01:21 PM


Originally Posted by hyperion (Post 7682010)
Thanks, Andrew. Great post.

StopTech put a lot of design work into limiting flex on their calipers. I talked to their development engineer a few years ago and he had quite a bit to say about it. One of the things he highlighted was that the 993TT (Red Lobster) calipers are some of the worst when it comes to flex. His impression was that Porsche made them big for show. (The newer monobloc calipers are supposedly much better.) An Alcon engineer had similar thoughts on just about all production calipers.

But anyway, as far as leading taper goes I think what I've seen so far is acceptable. I think I can get at least 4-6 track days out of a set of pads--and this is with 3100+ lbs and 430 RWHP.

The radial taper is still a bummer. I will measure the location of the pistons, but I'm pretty sure it's due to flex. Perhaps pad switching will address the issue on the track--we shall see.

But all of this aside, I think there's a point that RB has made to me that's worth repeating: they are not trying to design the ultimate brake kit for track use. They're trying to provide a good value performance ratio. If--and that's still and if--I can get the kinks worked out, I think this kit is capable of running consistently into the high 1:30's at Laguna Seca without ducting. That's faster than a lot of very expensive cars, including a brand new GT3 RS driven by Speed GT champion Johannes van Overbeek (who I paced for a lap at Laguna in December. He's quick.)

Not bad. But like I said, I have to get all the kinks out first.

-ch

Radial taper is hard to get rid of with pad swapping of course since you can't get the inside to the outside. When Damian had that issue he was burning through the pads and rotors quicker than he wanted for sure. He also talked to a Stoptech engineer and came to the same conclusion you did, they are much better calipers with regard to flex. Wasn't the ultimate solution for him, but his brake system is in much better shape now that he's using them.

It makes sense what the engineers are saying too, 90-95% of the people who buy the cars with the OEM brakes never track or use them in any matter that even stresses the brake system at all. Why spend the extra 80% of the development costs to get that last 20% of performance that will never get used by all those people and subtracts so much from the bottom line?

I suspect that even though the big reds flex (they're 15+ year old tech at this point!) they are rigid enough for my car since I'm running only 340ish hp. It wouldn't surprise me if I had to upgrade if I went up to 400hp as I told you before. I suspect that Damian's car is also getting close to the unacceptable range as well, however the one thing we have going for us is that our cars are all substantially lighter than what the brakes were originally designed for.

I think you are correct in saying that if you can figure the last couple items out the RB setup is a good value for you and everyone else. Just is taking longer to get there than everyone wants.

gnx7 02-04-08 09:21 PM

Any progress/update on this thread? Cracked rotor resolution?

gracer7-rx7 02-12-08 11:08 AM

Can someone recommend a good track pad for an intermediate level driver with this brake setup? Both RB compound or preferably Hawk.

I'm struggling with the decision on this new RB setup...

I'm using Hawk HPS on the street.

Thanks.

Howard Coleman 02-12-08 02:21 PM

gracer, i don't have an answer for you but i just want to mention a recent conclusion i have reached re brake pads...

if i were a brake co selling brake systems and pads i would not offer a pad that could be considered dual purpose.... that is street and track.

i don't think there is such a thing. the track asks alot from a pad and should it degrade heading into a heavy braking zone i would not want to be the driver pushing on the middle pedal.

race is race.

street is street.

is there a continuum re degradation temperature that you can ride between street and track?

sure but

the bottom line is that you are going to step over the temperature line once you get ontrack.

there's just no such thing as a little speed. running dual purpose pads ontrack would simply be answering the question how many laps before the self destruct... i have no interest in answering that question.

so for 08 as i look into the test sessions and ontrack stuff. i am going to be running RB's suggestion for racepads.

i really like my ET800s on the street but they aren't going ontrack. i like the 700s and 500s too. see above.

i would also mention that RB did clearly try to make the point that everything below racepads was a compromise....

IMO, you just can't compromise ontrack.

hc

gracer7-rx7 02-12-08 02:57 PM

Sorry if I wasn't clear. I definitely am NOT looking for a dual purpose pad. That is why I bought the HPS to use for street driving. I need to select a dedicated track pad but don't have a lot of experience with the FD on track yet. I've only done 3 events with it.

In the past, I've mostly driven underpowered, momentum cars like the A1 VW, NA FC, stock TurboII FC, Miata, turbo Miata and e36 BMW 325 so brakes were never really much of a concern at my driving level (typically Group 3) and the tracks I drove on (Lime Rock mostly). Then I started racing karts and only got back on track in 2007.

Hawk HP+ probably won't be sufficient
Hawk Blacks are the next step up but seem to be more of a race pad used by ITS drivers. Not sure if the temp range is sufficient for the speeds an FD will hit on faster Cali tracks.
HT10 seem good but hard core dudes like GooRoo use them and I know my skills and confidence will take some time to get back to that point so I'm not sure if that is beyond what I can use.

Experience is the ultimate teacher and I definitely lack that when it comes to brakes. In the past they only slowed me down. :) - karting joke....

Silver7 02-12-08 03:54 PM

I would not even consider Hawk Blacks for track use. I have used blues for quite a few years and don't even think they are adequate. I am trying HT10s next year.

hyperion 02-12-08 10:02 PM

Rick is probably too busy staring longingly at his new race car (sorry, Rick, I had to say it) but he ran HT-10's at the Laguna event last December. His car is around 300HP and he felt they performed very well. I was impressed with the feel as a passenger.

I ran the more aggressive DTC-70's up front on my car (430 RWHP) and I thought they were excellent. Hawk said they were worried that I wouldn't get them up to their operating temp! But my testing suggests that they are well suited to the higher HP cars very well.

I ran HT-10s in the rear because they are the only ones available. So for the requirements you listed, I think the HT-10s would be great. If you over-brake them, try HT-14s in the front.

-ch

Scrub 02-12-08 11:07 PM

I'm sure this has been covered but can someone make a recommendation for front and rear pads for street use. I'm using the stock sized rear rotors. Sorry, but I couldn't find anything.

-Dan

ptrhahn 02-13-08 09:00 AM

I still think PFC pads are the best if you can afford them, but unfortunately they don't come in stock FD sizes anymore. I use the 01's on the front w/ my StopTechs, and pair them with whatever high-torque compound I can get my hands on for the rear. I've used 97's (when available), and Nicks competition compounds. I'd love to see a GB or limited run of 01 compound FD rears... I think PFC would need 50 sets ordered or so.

gracer7-rx7 02-13-08 09:54 AM

Thanks gents.

reawolfe 02-13-08 11:12 AM

I have run HT-10s on two days at Laguna and was very impressed with the stopping power and lack of fade. I was not as pleased with the ET-800s.

I am in the habit of not swapping pads between track and street, so the ET-10s are on my car today. Sure, they don't work quite as well when they are cold but the massive stopping power afforded by the RB system more than compensates. I don't even notice it. The only downside is that they do generate copious amounts of nasty black dust that sticks like epoxy to everything and they tend to be a little noisy... I like to think it adds character :)

Pardon me but I have to get back to gazing longingly at my new race car now.

-Rick

hyperion 02-14-08 10:52 AM

^^^^^ :D

-ch

ptrhahn 02-14-08 11:43 AM

This was the aspect I was wondering about with HT-10's.

Years ago I put Hawk Blues on my car—NEVER again. The awful black dust; needing to "pam" your wheels; worrying that it'll rain (turns the already difficult black dust into petrified cement); Scrubbing the hell out of my wheels/car after an event. Plus cold braking worked, but tore my rotors to shreds.... and it really freaked people out on the road to see a shower of sparks coming off your front wheels.

I'll GLADLY pay more for PFC's. I was half hoping that the newer Hawk compounds are better, but it doesn't sound like it.




Originally Posted by reawolfe (Post 7861912)
The only downside is that they do generate copious amounts of nasty black dust that sticks like epoxy to everything and they tend to be a little noisy... I like to think it adds character :)


hyperion 02-14-08 12:49 PM


Originally Posted by ptrhahn (Post 7866690)
This was the aspect I was wondering about with HT-10's.

Years ago I put Hawk Blues on my car—NEVER again. The awful black dust; needing to "pam" your wheels; worrying that it'll rain (turns the already difficult black dust into petrified cement); Scrubbing the hell out of my wheels/car after an event. Plus cold braking worked, but tore my rotors to shreds.... and it really freaked people out on the road to see a shower of sparks coming off your front wheels.

I'll GLADLY pay more for PFC's. I was half hoping that the newer Hawk compounds are better, but it doesn't sound like it.

Peter, I've had the same experience with Blues. FWIW, the DTC-70 (Hawk's most aggressive race compound) seems to wipe right off the finish of the car, even when I've been lazy and let it sit for a day or two. And the cold pads don't seem wreck the rotors at all, although they SQUEAL LIKE CRAZY at low speed. I agree that the PFC is a great pad, but unfortunately the RB guys suggest that the PFC compounds don't do well with their rotors.

The Blues really were the worst of any pad by a long shot.

-ch

Scrub 02-14-08 03:14 PM

I'm looking for a street pad that doesn't dust like crazy either, I forgot the mention that above. Sorry for my lack of knowledge but who makes "PFC" pads?

-Dan

Eggie 02-14-08 03:29 PM

Performance Friction

reawolfe 02-15-08 10:55 AM

I have not noticed any unusual wear from using the HT-10s on the street.



Originally Posted by ptrhahn (Post 7866690)
This was the aspect I was wondering about with HT-10's.

Years ago I put Hawk Blues on my car—NEVER again. The awful black dust; needing to "pam" your wheels; worrying that it'll rain (turns the already difficult black dust into petrified cement); Scrubbing the hell out of my wheels/car after an event. Plus cold braking worked, but tore my rotors to shreds.... and it really freaked people out on the road to see a shower of sparks coming off your front wheels.

I'll GLADLY pay more for PFC's. I was half hoping that the newer Hawk compounds are better, but it doesn't sound like it.


ptrhahn 02-15-08 07:17 PM

Dan, for the street, I believe that Axxis makes a "deluxe" pad, that's "down" a grade from the Ultimate, but specifically dusts less.

PFC's that I have experience with are track pads, not sure about their street compounds.




Originally Posted by Scrub (Post 7867533)
I'm looking for a street pad that doesn't dust like crazy either, I forgot the mention that above. Sorry for my lack of knowledge but who makes "PFC" pads?

-Dan



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