RR Racing Brake Development -- Competition and Street

[maregt]

Originally Posted by gskv

This thread is 40 pages long and I still don't have any information regarding brake bias information from RR vs. the Essex kit

I want to pull the trigger but this isn't quite feel right...

Hi, you should send them an email with a specific question, I'm sure they can give you the answer you are looking for

[JRitt]

Originally Posted by gskv

This thread is 40 pages long and I still don't have any information regarding brake bias information from RR vs. the Essex kit

I want to pull the trigger but this isn't quite feel right...

I asked for detailed specs and bias information to be published about a year ago. I was told "go find it on their website." Then I was accused of being a bad person for posting a technical question in a competitor's thread. I thought a technical question in a technical thread was valid.

[sickmint79]

Originally Posted by Joe-G

I've come across 3 different sources of information, and all 3 have arrived at different results... -__-

1. One source claims that the sport kit moves the bias forward, significantly less than Stage 1-4.

2. Another source says that stage 1-4 is less than the sport kit.

3. Third source states that bias is the same for the sport kit and stage 1-4.

Im so confused lol...

(this is for aftermarket front, and OE rears)

i don't know if one of those was another of my articles before i had the blog (it was on kinja) - in any case i am transparent and showing you the numbers and calculators i used to arrive at my conclusions, it would be interesting to read someone else's article which shows different conclusions and how they arrived at them.

[sickmint79]

Originally Posted by Lynxis

RR-Racing has more or less abandoned this thread now that the products are out. To be fair, this is a development thread and now development is over so there is that but considering the competition is still somewhat active on the forums, well after releasing their products, maybe that is something to keep in mind.

When someone ran the numbers based on my preliminary measurements for the sport performance kit, they found it was extremely close to stock, less than 2% difference in brake torque. Obviously, that shouldn't affect anything for anyone but this was eyeballed with a crappy ruler and could be inaccurate so I had hoped to take more accurate measurements before the snow flew but I never got time so now I'm waiting until spring.

The numbers I got don't match any the published numbers for these calipers from Wilwood so someone (A member of the competition mind you) ran the numbers based on the closest options provided by Wilwood and all of the options are within about 5% of stock. This represents a worst case scenario for these braking systems and IMO, is still fine for the average driver and light track use but I admit a more demanding driver might find this insufficient.

note the difference between the light user newer driver with WW front only vs. WW front and rear. i wouldn't argue the amount the former shifts bias forward no big deal for anyone, just because the number "seems to be small"

[jamal]

Originally Posted by sickmint79

i don't know if one of those was another of my articles before i had the blog (it was on kinja) - in any case i am transparent and showing you the numbers and calculators i used to arrive at my conclusions, it would be interesting to read someone else's article which shows different conclusions and how they arrived at them.

The issue I saw was using the overall diameter of the rotor. Effective diameter would be where the center of the pistons are. Short of measuring that, you could probably get very close by taking the pad height and then subtracting half plus a mm or two from the OD of the rotor.

I suppose using OD is somewhat close, in reality pushes the bias forward, because the ED on the rear, with smaller pistons and shorter pads, is actually closer to the outside of the rotor compared to the front. It would also be less accurate comparing a bbk with big rotors and smaller pistons.

An old legacy guy has a brake math spreadsheet with the effective diameters of a lot of stock brakes. I have been meaning to make some modifications to it with some aftermarket stuff and more cars.

http://www.main.experiencetherave.co.../brakemath.xls

[Lynxis]

I e-mailed Simon at RR Racing and he has provided me the relevant Wilwood caliper part numbers for each of the kits.

Stage 1/3: 120-11779 - http://www.wilwood.com/Calipers/Cali...o=120-11779-BK

Piston Specifications
Piston 1 Bore(In): 1.62
Piston 2 Bore(In): 1.12
Piston 3 Bore(In): 1.12
Total Piston Area (in²): 4.04



Stage 2/4: 120-13235, 120-13236 - http://www.wilwood.com/Calipers/Cali...emno=120-13235, http://www.wilwood.com/Calipers/Cali...emno=120-13236

Piston Specifications
Piston 1 Bore(In): 1.62
Piston 2 Bore(In): 1.12
Piston 3 Bore(In): 1.12
Total Piston Area (in²): 4.04



Sport Performance: 120-11132 - http://www.wilwood.com/Calipers/Cali...emno=120-11132

Piston Specifications
Piston 1 Bore(In): 1.62
Piston 2 Bore(In): 1.62
Piston 3 Bore(In):
Total Piston Area (in²): 4.12

For anyone who feels like running the numbers again.

[jamal]

That's pretty useful- they have a diagram with the pad dimensions, which are about the same for all three calipers- just a different thickness.

So pad material is about 43mm high. Divide that by two, add 1-2mm because the edge of the pad will not be exactly with the edge of the rotor, and I would call the effective radius whatever the rotor diameter divided by 2 minus 23mm.

It assumes the centerline of the pistons lines up with the center of the pad material but I don't think it would be off by much. Closer than using the OD of the rotor anyway.

Tonight if I feel like it I'll look up the rotor diameters and play around with the brake math spreadsheet. Guess I could even line the rotor, pad, and caliper up in cad and see what I get for effective radius that way since willwood provides the drawings.

[Evil Rocky]

These look very promising. I have to check if these can clear my wheels. I would love these.

[Irace86]

I'm running bp 10's for a while now. At first there was lots of squeal but there is much less since performing a second bleed in the system. Apparently I hadn't bled the system completely, most likely because air was trapped in the ABS system, but after activating the ABS over a few months I was able to bleed out more air, and now there is minimal squealing. I will likely perform another bleed in a few months to just make sure.

I have a few newb questions, maybe @Cartman or someone can help:

1. Are these pads normal pads, sporty street pads, street/track pads or entry level track pads? Considering they have BP 20's and 30's and stuff, I'm guessing entry level track pads, or some type of street/track pad.

2. Are most people who daily drive their car running a track or street/track pad, or are they running a normal pad like OEM style on the street, and then swapping for the track? I am looking to probably get some OEM style pads for the street.

3. Again noob question, but is it normal to get poor braking feel in the wet with bp10's (if they are track pads) or with track pads in general? I feel like these pads stop worse than OEM pads in the rain on the street. I have never really got them hot in the rain or used them on the track in the rain, so I don't know how much they change with heat, but I can tell improvement once they begin to heat up, yet like I said, I don't know if they equal dry weather performance or equal OEM pad abilities in the rain.

4. Does anyone make an OEM style (material) pad for these calipers? I saw @Cartman you said I could run a larger pad with the Ferodo 3116 pads. I'm guessing these are track pads; I need to see if they are medium or heavy use pads. Do you have a suggestion for a OEM/street pad of the larger dimension?

[Lynxis]

Originally Posted by Irace86

I'm running bp 10's for a while now. At first there was lots of squeal but there is much less since performing a second bleed in the system. Apparently I hadn't bled the system completely, most likely because air was trapped in the ABS system, but after activating the ABS over a few months I was able to bleed out more air, and now there is minimal squealing. I will likely perform another bleed in a few months to just make sure.

I have a few newb questions, maybe @Cartman or someone can help:

1. Are these pads normal pads, sporty street pads, street/track pads or entry level track pads? Considering they have BP 20's and 30's and stuff, I'm guessing entry level track pads, or some type of street/track pad.

2. Are most people who daily drive their car running a track or street/track pad, or are they running a normal pad like OEM style on the street, and then swapping for the track? I am looking to probably get some OEM style pads for the street.

3. Again noob question, but is it normal to get poor braking feel in the wet with bp10's (if they are track pads) or with track pads in general? I feel like these pads stop worse than OEM pads in the rain on the street. I have never really got them hot in the rain or used them on the track in the rain, so I don't know how much they change with heat, but I can tell improvement once they begin to heat up, yet like I said, I don't know if they equal dry weather performance or equal OEM pad abilities in the rain.

4. Does anyone make an OEM style (material) pad for these calipers? I saw @Cartman you said I could run a larger pad with the Ferodo 3116 pads. I'm guessing these are track pads; I need to see if they are medium or heavy use pads. Do you have a suggestion for a OEM/street pad of the larger dimension?

1. They are considered a dual purpose street/track pad. I find them mostly quiet on the street and I haven't personally experienced any brake fade on track but I suspect that is more because the calipers and rotors provide a nice big heat sink and I'm in Canada and avoid events during the hottest weeks of the summer due to running without an oil cooler. They do dust like mad though so prepare to be cleaning your wheels regularly.

Edit: Also, they don't last long and I'm told the BP20's are no better. I used around 75% of my pad material this summer with 3 track days, 6 autocross events and approximately 5000kms of daily driving. I expect that they will last the winter for me and that's it. I've got a set of EBC Yellowstuff and Winmax W5 pads to swap in the spring though. Thinking I'll daily on the Yellowstuff and track on the Winmax but we will see.

2. I can't say what most people do because this varies more based on what someone wants from their brake pads. Someone who is new to tracking or only tracks only once in a while and isn't interested in swapping pads for every event might prefer a dual purpose brake pad to make life easy. Someone who wants ultimate stopping power and fade resistance will go for a dedicated track pad and either live with the noise and dust on the street or swap it out between events.

3. This one is hard to answer. Personally, I haven't noticed anything in particular with my BP10s in the rain other than they tend to squeal a bit when wet compared to when dry but they perform like normal. I've even been driving with them all winter and have noticed no change in braking performance. I will note that after beating on them on track for a day and getting used to the hot bite and then letting them cool off, I find the cold bite very poor. I've noticed this after every track day. After a few days, I stop noticing it but I'm not sure if I just get used to it or if it actually improves. Seeing that you're in Cali, I just wonder if your ambient temperatures are high enough that you're starting to get into the hot bite most of the time and it only cools off enough to feel true cold bite when it rains. I can't say for sure though.

4. I know you can get Winmax W1, Hawk HPS and EBC Greenstuff which are all OEM like pads for the Wilwood calipers and I'm sure there are plenty of other options too. Most manufacturers make pads in the 7420/7416 shapes although special request/orders usually need to be made for them.

[Cartman]

Originally Posted by Irace86

I'm running bp 10's for a while now. At first there was lots of squeal but there is much less since performing a second bleed in the system. Apparently I hadn't bled the system completely, most likely because air was trapped in the ABS system, but after activating the ABS over a few months I was able to bleed out more air, and now there is minimal squealing. I will likely perform another bleed in a few months to just make sure.

I have a few newb questions, maybe @Cartman or someone can help:

1. Are these pads normal pads, sporty street pads, street/track pads or entry level track pads? Considering they have BP 20's and 30's and stuff, I'm guessing entry level track pads, or some type of street/track pad.

2. Are most people who daily drive their car running a track or street/track pad, or are they running a normal pad like OEM style on the street, and then swapping for the track? I am looking to probably get some OEM style pads for the street.

3. Again noob question, but is it normal to get poor braking feel in the wet with bp10's (if they are track pads) or with track pads in general? I feel like these pads stop worse than OEM pads in the rain on the street. I have never really got them hot in the rain or used them on the track in the rain, so I don't know how much they change with heat, but I can tell improvement once they begin to heat up, yet like I said, I don't know if they equal dry weather performance or equal OEM pad abilities in the rain.

4. Does anyone make an OEM style (material) pad for these calipers? I saw @Cartman you said I could run a larger pad with the Ferodo 3116 pads. I'm guessing these are track pads; I need to see if they are medium or heavy use pads. Do you have a suggestion for a OEM/street pad of the larger dimension?

1) I never used the BP10's so I can't really help you there, but I had the BP20's and was not a fan of them. The felt like they had no bite. Both BP10 and BP20 are considered hybrid street/track pads.

2) I switched to EBC greenstuff for DD since its the only pad I've been able to get that doesn't squeal like a raped monkey, but it did require the use of the Wilwood shims plus the included anti squeal tape from EBC. I plan on testing Ferodo DS1.11 this year for the track along with an old set of Raybestos ST45 I have for the rear.

3) I didn't use the BP's long enough to experience them in the rain, Sorry I can't help on this. But I have not noticed any change in braking performance with the EBC pads in the rain.

4) I think EBC has almost all their pads in 7420 size, but I've read that the Carbotech 1521 are excellent pads for DD from people running the AP racing kit, which uses the same wilwood pad shape. As far as running the taller pads, I would advice against it. After 3 events I noticed that my pads are wearing much faster at the top than the bottom (e.g. Pad material -> /| <- backing plate), most likely due to the fact that the pistons only touch the upper half of the pad, also could be the cause of why I could never get them to stop squealing.

[Irace86]

Originally Posted by Lynxis

...

I think you might be right about the performance of the pads in wet conditions being more related to the cold vs the fact that they are wet, and also it could be in my perception of the difference of the bite that goes with a warm pad.

Originally Posted by Cartman

...

Thanks for the info on the longer pads. To be honest, it was mostly for aesthetic changes. I'm guessing you had your resurfaced or had little wear when you switched to the other pads, right? It isn't a lip that is still creating the uneven wear, right?

I think I'll just stick with these for now, and when it is time to buy new ones maybe try a dedicated street pad and a hybrid or a race only pad. Thanks.

[Cartman]

Originally Posted by Irace86

I think you might be right about the performance of the pads in wet conditions being more related to the cold vs the fact that they are wet, and also it could be in my perception of the difference of the bite that goes with a warm pad.



Thanks for the info on the longer pads. To be honest, it was mostly for aesthetic changes. I'm guessing you had your resurfaced or had little wear when you switched to the other pads, right? It isn't a lip that is still creating the uneven wear, right?

I think I'll just stick with these for now, and when it is time to buy new ones maybe try a dedicated street pad and a hybrid or a race only pad. Thanks.

Yeah, i only had the surface rust when i first put them on... Since i used the bp's for like 2 weeks, i think had the disk had a lip, the pad would have come out with a groove on it by now.

[sickmint79]

Originally Posted by jamal

The issue I saw was using the overall diameter of the rotor. Effective diameter would be where the center of the pistons are. Short of measuring that, you could probably get very close by taking the pad height and then subtracting half plus a mm or two from the OD of the rotor.

I suppose using OD is somewhat close, in reality pushes the bias forward, because the ED on the rear, with smaller pistons and shorter pads, is actually closer to the outside of the rotor compared to the front. It would also be less accurate comparing a bbk with big rotors and smaller pistons.

An old legacy guy has a brake math spreadsheet with the effective diameters of a lot of stock brakes. I have been meaning to make some modifications to it with some aftermarket stuff and more cars.

http://www.main.experiencetherave.co.../brakemath.xls

ah yes, i noted this in the article, i use OD and the same pad size for all as it's all the information i've got to go off of. it's hard enough to get piston sizes let alone for this stuff. since the same error as committed across the board though i consider it fair to compare kit A to kit B though. i'm not sure more accurate numbers would affect those overall conclusions.

Originally Posted by Lynxis

I e-mailed Simon at RR Racing and he has provided me the relevant Wilwood caliper part numbers for each of the kits.

Stage 1/3: 120-11779 - http://www.wilwood.com/Calipers/Cali...o=120-11779-BK

Piston Specifications
Piston 1 Bore(In): 1.62
Piston 2 Bore(In): 1.12
Piston 3 Bore(In): 1.12
Total Piston Area (in²): 4.04



Stage 2/4: 120-13235, 120-13236 - http://www.wilwood.com/Calipers/Cali...emno=120-13235, http://www.wilwood.com/Calipers/Cali...emno=120-13236

Piston Specifications
Piston 1 Bore(In): 1.62
Piston 2 Bore(In): 1.12
Piston 3 Bore(In): 1.12
Total Piston Area (in²): 4.04



Sport Performance: 120-11132 - http://www.wilwood.com/Calipers/Cali...emno=120-11132

Piston Specifications
Piston 1 Bore(In): 1.62
Piston 2 Bore(In): 1.62
Piston 3 Bore(In):
Total Piston Area (in²): 4.12

For anyone who feels like running the numbers again.

i certainly don't recall what i used as source now, but i had very different sport kit front numbers in my article - 1.49606x2 - which actually kept bias quite stock looking. however with the above numbers (i use 328mm = 12.9134 rather than 12.8 for rotor) - i'm ending up with 0.733, and the most forward of all their front only kit options then.