Anyone have any brake questions?
#581
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Rear sport rotors or rotors and calipers? Very limited pad availability for rear sport calipers. Better to use 1.8 rear calipers and 949 brackets with sport rear rotors.
Regarding balance, it will depend on weight distribution, pad choice, and driving style. If you predominantly brake in a straight line a square pad setup would be where I start. I'd put some less grippy tires on it and do some testing of the balance, starting neutral and adding prop valve if necessary. If you can't get it right with the valve, stagger the pad compounds and start neutral and add valve adjustments as necessary. I don't think it will be as far out as you have been led to believe.
Regarding balance, it will depend on weight distribution, pad choice, and driving style. If you predominantly brake in a straight line a square pad setup would be where I start. I'd put some less grippy tires on it and do some testing of the balance, starting neutral and adding prop valve if necessary. If you can't get it right with the valve, stagger the pad compounds and start neutral and add valve adjustments as necessary. I don't think it will be as far out as you have been led to believe.
#582
Crusher ran the same brakes running XP12 front, XP8 rear and a prop valve for fine tuning. We ran NA8 calipers though. Sport rear calipers have larger pistons that make it difficult to balance with compounds. NA8/NB1 rear calipers will fit the sport brackets and rotor.
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#583
11/10.9 is OK up to about 200whp on hard compound race tires or lower power with Hoosiers. You'll need to run a compound stagger of about .15 Mu.
Crusher ran the same brakes running XP12 front, XP8 rear and a prop valve for fine tuning. We ran NA8 calipers though. Sport rear calipers have larger pistons that make it difficult to balance with compounds. NA8/NB1 rear calipers will fit the sport brackets and rotor.
Crusher ran the same brakes running XP12 front, XP8 rear and a prop valve for fine tuning. We ran NA8 calipers though. Sport rear calipers have larger pistons that make it difficult to balance with compounds. NA8/NB1 rear calipers will fit the sport brackets and rotor.
On my personal car i run an square compound. that way I don't have strange Mu variances with heat changes.
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#584
why would you want to run a compound stagger? and how did you get to the number that's 37.5% less rear Mu? your recommending this set up i'm just wondering why your killing off the rear brakes by 37.5% on a car that is engineered to have a heavy front bias.
On my personal car i run an square compound. that way I don't have strange Mu variances with heat changes.
On my personal car i run an square compound. that way I don't have strange Mu variances with heat changes.
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#586
i was apart of the team that won these championships. 100% brake focused development of professional teams.
2011 PFC Champions
Tony Stewart – NASCAR Sprint Cup Series
Ricky Stenhouse, Jr. – NASCAR Nationwide Series
Austin Dillon – NASCAR Camping World Truck Series
Ron Silk - NASCAR Whelen Modified Tour
Andrew Morrissey - American Speed Association® Kwik Trip Midwest Tour
Dennis (Rambo) Franklin – Carolina Clash Super Late Model Series
Eddie Carrier Jr. - ADRA Dirt Late Model Championship
Chris Madden - Schaeffer Oil Southern Nationals Series Champion
Matt Sheppard - Super DIRTcar Series Big Block
Kevin Cornelius - Late Model Champion, Sunset Speedway
Andrew Gresel - Late Model Champion, Delaware Speedway
Kenny Tremont - Lebanon Valley and Glen Ridge Motorsports Park Dirt Modified
Chad Brachman – Ransomville Speedway
Billy Decker – ROC Modified Tour
Road Racing
Scott Pruett and Memo Rojas - GRAND-AM Rolex Sports Car Series
Patrick Long - Pirelli World Challenge GT
Etienne Borgeat - Castrol Canadian Touring Car
Will Power - IndyCar Series Road Course Drivers Champion
Scott Dixon - IndyCar Series Oval Drivers Champion
Dario Franchitti - IndyCar Series Overall Driver’s Champion
Petri Suvanto - Cooper Tires Presents USF2000 National Championship Powered by Mazda
Tristan Vautier – Star Mazda
Remy Audette – F2000 Championship Series
David Higgins/Subaru USA - Rally America Open Class
Travis Hanson – Rally America Super Production Class
Tony Ave - SCCA Pro Racing Trans-Am
Michael Lewis - GT1 SCCA National Champion
John Black - GT3 SCCA National Champion
Scott Tucker - STO SCCA National Champion
Revere Greist - FC SCCA National Champion
Brian Novak - Formula B SCCA National Champion
Michael Mallinen - Formula Atlantic SCCA National Champion
Tom Bootz - D-Sports SCCA National Champion
Ricardo Vera - IMSA LITES L-1 Driver’s Championship
Eurosport - IMSA LITES L-1 Team Championship
Robert Sabato - IMSA LITES L-2 Driver’s Championship
Lee Davis - Cayman Interseries Driver’s championship
Lee Davis / Ryan Eversley - Cayman Interseries Enduro Championship
Tim Fox - Intercontinental Trophy Cup P1 Drivers Championship
Josef Newgarden - Firestone Indy Lights Driver’s champion
Larbre Competition - Intercontinental Le Mans Cup GTE Am
Japan
Masataka Yanagida and Ronnie Quintarelli – Super GT GT500
Andre Lotterer - Formula Nippon
Yuhi Sekiguchi – Formula 3 B-MAX F308
Yuhi Sekiguchi – Formula 4 B-MAX ENGINEERING
Tomoya Hoshino - Z Expert trophy Gr.A class
That was my first year. talk to me.
2011 PFC Champions
Tony Stewart – NASCAR Sprint Cup Series
Ricky Stenhouse, Jr. – NASCAR Nationwide Series
Austin Dillon – NASCAR Camping World Truck Series
Ron Silk - NASCAR Whelen Modified Tour
Andrew Morrissey - American Speed Association® Kwik Trip Midwest Tour
Dennis (Rambo) Franklin – Carolina Clash Super Late Model Series
Eddie Carrier Jr. - ADRA Dirt Late Model Championship
Chris Madden - Schaeffer Oil Southern Nationals Series Champion
Matt Sheppard - Super DIRTcar Series Big Block
Kevin Cornelius - Late Model Champion, Sunset Speedway
Andrew Gresel - Late Model Champion, Delaware Speedway
Kenny Tremont - Lebanon Valley and Glen Ridge Motorsports Park Dirt Modified
Chad Brachman – Ransomville Speedway
Billy Decker – ROC Modified Tour
Road Racing
Scott Pruett and Memo Rojas - GRAND-AM Rolex Sports Car Series
Patrick Long - Pirelli World Challenge GT
Etienne Borgeat - Castrol Canadian Touring Car
Will Power - IndyCar Series Road Course Drivers Champion
Scott Dixon - IndyCar Series Oval Drivers Champion
Dario Franchitti - IndyCar Series Overall Driver’s Champion
Petri Suvanto - Cooper Tires Presents USF2000 National Championship Powered by Mazda
Tristan Vautier – Star Mazda
Remy Audette – F2000 Championship Series
David Higgins/Subaru USA - Rally America Open Class
Travis Hanson – Rally America Super Production Class
Tony Ave - SCCA Pro Racing Trans-Am
Michael Lewis - GT1 SCCA National Champion
John Black - GT3 SCCA National Champion
Scott Tucker - STO SCCA National Champion
Revere Greist - FC SCCA National Champion
Brian Novak - Formula B SCCA National Champion
Michael Mallinen - Formula Atlantic SCCA National Champion
Tom Bootz - D-Sports SCCA National Champion
Ricardo Vera - IMSA LITES L-1 Driver’s Championship
Eurosport - IMSA LITES L-1 Team Championship
Robert Sabato - IMSA LITES L-2 Driver’s Championship
Lee Davis - Cayman Interseries Driver’s championship
Lee Davis / Ryan Eversley - Cayman Interseries Enduro Championship
Tim Fox - Intercontinental Trophy Cup P1 Drivers Championship
Josef Newgarden - Firestone Indy Lights Driver’s champion
Larbre Competition - Intercontinental Le Mans Cup GTE Am
Japan
Masataka Yanagida and Ronnie Quintarelli – Super GT GT500
Andre Lotterer - Formula Nippon
Yuhi Sekiguchi – Formula 3 B-MAX F308
Yuhi Sekiguchi – Formula 4 B-MAX ENGINEERING
Tomoya Hoshino - Z Expert trophy Gr.A class
That was my first year. talk to me.
__________________
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#587
Impressive
I pointed out the results as way to illustrate that it was not a inadequately engineered guess. You asked if we deliberately chose a lower .mu pad to reduce brake torque in the rear and balance the system, which you and everyone reading the post already knows the answer to. So I didn't answer that question. I instead validated our setup by stating that it works just fine, by swinging it out.
I have posted this elsewhere, perhaps in this thread, we recommend NA8/NB1 rear rotors calipers when using 11" or Sport fronts. We only suggest Sport rears when paired with 11.75" fronts. We made the 11/10.9 work that year by playing with pad compounds, and it proved a solid workaround.
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#588
You drove the car, were present at every test session, personally collected the data and made the final decision on how the brake system was configured?
Impressive
I pointed out the results as way to illustrate that it was not a inadequately engineered guess. You asked if we deliberately chose a lower .mu pad to reduce brake torque in the rear and balance the system, which you and everyone reading the post already knows the answer to. So I didn't answer that question. I instead validated our setup by stating that it works just fine, by swinging it out.
I have posted this elsewhere, perhaps in this thread, we recommend NA8/NB1 rear rotors calipers when using 11" or Sport fronts. We only suggest Sport rears when paired with 11.75" fronts. We made the 11/10.9 work that year by playing with pad compounds, and it proved a solid workaround.
Impressive
I pointed out the results as way to illustrate that it was not a inadequately engineered guess. You asked if we deliberately chose a lower .mu pad to reduce brake torque in the rear and balance the system, which you and everyone reading the post already knows the answer to. So I didn't answer that question. I instead validated our setup by stating that it works just fine, by swinging it out.
I have posted this elsewhere, perhaps in this thread, we recommend NA8/NB1 rear rotors calipers when using 11" or Sport fronts. We only suggest Sport rears when paired with 11.75" fronts. We made the 11/10.9 work that year by playing with pad compounds, and it proved a solid workaround.
For the record i only keep the rear sport rotors only to keep a parking brake. i was once told "real race cars don't have parking brakes" but watching your car roll down hill is annoying. when teamed up with the 11.75" kit the rear sport brakes are already behind the eight ball. It would be a safe combination and work out well if you have a square compound. aftermarket prop vales are always a must.
it is strange.. with our spec miata teams with PFC pads they can run a square set up PFC11/11 combo. The teams that run a hawk/carbo they go for a dtc60/30 split. Mind you they are jumping the brakes a lot mid-turn to avoid collisions. My only conclusion is that the PFC has a softer bite, so they can jab a brake pedal mid tun without unsettling the car. as with the hawk/carbo maybe the bight is too high. So your left reducing the TQ to try and make up for the aggressive bite. That would in the end hurt performance of the braking system. I don't work with carbos so i'm unsure.
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#592
Bobcat is a 10 year old name for the 1521 compound which is designed for street use. Not remotely a race pad. 1521's don't work on track regardless of brake setup unless you're coasting around 15s slower then the car is capable of. Whichever brand pad you choose for track use, I suggest a lower .mu pad in rear by 10-15%, based on our experience with very similar setup.
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#593
Hello everyone!
First, thank you VERY much for starting this hugely informative/educative thread… I’m learning a lot and try to « get it » ;-)… After 30 pages of reading, I hope I begin to understand what are the very good/best thing to do (11”75 front, 11” rear, PFC pads and so on..)…
Here is my 1st question: What improvement would you do with a US$500 budget? With US$ 1000? I know, it’s not massive, but the answer would be too easy with $1500 or more… Even racing team have to work winthin a budget!
To guide you in your answer, my car is a NB 10AE with stock 1.8l engine (turbo is on the shelf, should be in the engine bay in the coming …18 months or so), weight is 2400lbs ( under 1100kg driver onboard) with a modified chassis:
-lowered (3.9" front pinch weld height, with a positive rake),
-polypro bushes, Bilstein B6 shocks (OEM on the 10th AE),
-frame rail and hard dog Roll bar.
… And Toyo R888 tires
On the brake side, it’s all OEM except for SS brake lines, DS2500 pads front (average mu 0.42) and Motul RBF 600. So I still have the ABS and the not so good OEM “prop” valve which is hugely front bias.
The car is 80% trackday car (no racing), the 20% left is to road test the mods I do and keep the car running once/twice a month…
Regarding my 1st question, I assume removing the ABS fuse, getting a “proper” proportioning valve and fitting same pads 4 corners would be a start… I must state that, for now, I never felt I needed more brake as I’m still tuning my tail-braking, braking point, breaking modulation to increase max speed in corner (or: how to test one’s ball size...) but with much more power in sight, more stopping power will be certainly required.
Also, the miata/mx5 is equipped with floating caliper and I understand the principle… Could you explain what is a floating rotor?
Thank you very much…
First, thank you VERY much for starting this hugely informative/educative thread… I’m learning a lot and try to « get it » ;-)… After 30 pages of reading, I hope I begin to understand what are the very good/best thing to do (11”75 front, 11” rear, PFC pads and so on..)…
Here is my 1st question: What improvement would you do with a US$500 budget? With US$ 1000? I know, it’s not massive, but the answer would be too easy with $1500 or more… Even racing team have to work winthin a budget!
To guide you in your answer, my car is a NB 10AE with stock 1.8l engine (turbo is on the shelf, should be in the engine bay in the coming …18 months or so), weight is 2400lbs ( under 1100kg driver onboard) with a modified chassis:
-lowered (3.9" front pinch weld height, with a positive rake),
-polypro bushes, Bilstein B6 shocks (OEM on the 10th AE),
-frame rail and hard dog Roll bar.
… And Toyo R888 tires
On the brake side, it’s all OEM except for SS brake lines, DS2500 pads front (average mu 0.42) and Motul RBF 600. So I still have the ABS and the not so good OEM “prop” valve which is hugely front bias.
The car is 80% trackday car (no racing), the 20% left is to road test the mods I do and keep the car running once/twice a month…
Regarding my 1st question, I assume removing the ABS fuse, getting a “proper” proportioning valve and fitting same pads 4 corners would be a start… I must state that, for now, I never felt I needed more brake as I’m still tuning my tail-braking, braking point, breaking modulation to increase max speed in corner (or: how to test one’s ball size...) but with much more power in sight, more stopping power will be certainly required.
Also, the miata/mx5 is equipped with floating caliper and I understand the principle… Could you explain what is a floating rotor?
Thank you very much…
#594
it's hard to ignore 500 race cars using the same brakes. :P
but your right they do have very different requirements, and are not trying to set lap times on race day.
but your right they do have very different requirements, and are not trying to set lap times on race day.
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800.934.9112
703.430.3303
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#595
I didn't drive the cars. from all my work i learned to i avoided the drivers as best i could. i wanted to talk to the crew chiefs and the lead engineers. i wasn't present at every test, (some test yes, but not all). Data was sent to us by a team engineer or team owner, and sometimes communication with the driver was the only data we had. I leaned real quick how inaccurate driver data was. i developed a question asking pattern that lead me to the characteristics of how the car was handling. my findings coincided 50% of the time with what the driver was telling me. Most of the drivers think they know what is going on and have absolutely no clue. on some of the cars i personally did have the final recommendation on how the system was configured. PFC had a 5 man team for all of those championships. my field was grand-am, ALMS, PWC, club racing, and inside support for the NASCAR teams.
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703.430.3303
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#596
Can someone explain to me why there's such a disparity over brake bias recommendations? On one hand, you've got people recommending to take out the stock prop valve altogether on an otherwise stock setup, and on the other you've got track gurus running more aggressive pads on the front than the rear even with big brake kits.
Is it as simple as that you track guys are running such grippy tires that they can handle and/or need that much front brake during forward weight transfer?
On my street car, on moderate street tires, I definitely feel like the fronts lock prematurely on my square-padded, stock-braked setup. Am I wrong?
Is it as simple as that you track guys are running such grippy tires that they can handle and/or need that much front brake during forward weight transfer?
On my street car, on moderate street tires, I definitely feel like the fronts lock prematurely on my square-padded, stock-braked setup. Am I wrong?
#597
Is it as simple as that you track guys are running such grippy tires that they can handle and/or need that much front brake during forward weight transfer?
On my street car, on moderate street tires, I definitely feel like the fronts lock prematurely on my square-padded, stock-braked setup. Am I wrong?
On my street car, on moderate street tires, I definitely feel like the fronts lock prematurely on my square-padded, stock-braked setup. Am I wrong?
Note that in F1, Michael Schumacher used to adjust his prop valve to a different setting for EVERY CORNER. Obviously a Miata isn't an F1 car, but it demonstrates that there are a lot of factors going into it.
--Ian
#599
A lot of this is how a driver feels a particular pad combo works for them. Some read a recommendation and run with it as if it's the only possible pad combo that works. I've heard diametrically opposed opinions from 2 different sources regarding particular pads. In the end, if a particular combo works well for you and the car feels balanced then that's fine.
Super large brakes are fine if your budget allows and as the hp increases so does the speed and you need larger brakes to dissapate the heat effectively.
It would be interesting to see some actual test data for stopping distances with stock systems vs the 11.75 kits.
Super large brakes are fine if your budget allows and as the hp increases so does the speed and you need larger brakes to dissapate the heat effectively.
It would be interesting to see some actual test data for stopping distances with stock systems vs the 11.75 kits.
#600
How many stops are you going to do? Haha. The best proportioned of the stock setups with stockish grip will probably outperform a lot of the common track setups with stockish grip for a couple stops. Even stepping up to racing grip the best of the stock setups are going to stop better thank a large chunk of what HPDE bros run for a couple stops. But even the worse POS track bro setup you can come up with, like 11.75 from 1.6 rear with stock prop valve is going to outstop stock brakes at the end of a 20 session on the track.