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Old 10-27-2014, 09:18 AM   #61
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This post censored in order to slow to progress of knowledge entropy.

Last edited by Leafy; 10-27-2014 at 09:49 AM.
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Old 10-27-2014, 09:27 AM   #62
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Our cars actually have dual master cylinders, they're just the same diameter and in line so set spread sheet to both MCs the same diameter and the balance bar to 50/50 and thats it. No modifications there.
Leafy, Dude Stop flipping trolling. You flipping bomb in every thread and act like an expert. I want to see what teams you've worked with and how were your results. IF you haven't worked with ANY teams what cars have you built and what races have you won?

Yes Technically the miata's master cylinder has dual bores. It also uses a proportioning valve. it is not a "dual matercyclinder unit". IE with a balance bar. First thing our teams do is rip out the Master cylinder oem units, and replace it with a dual master cylinder + balance bar. Dual MC's provide much better feedback and without the use of a prop vales are able to accurately adjust brake bias.
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Old 10-27-2014, 09:38 AM   #63
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This post censored in order to slow to progress of knowledge entropy.

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Old 10-27-2014, 09:39 AM   #64
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I'll get some corner weights for you.

Leafy seems to get the same response on some other forums as well. Take him with a grain of salt.
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Old 10-27-2014, 09:44 AM   #65
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Your spreadsheet doesnt also do prop valves? You realize that prop valves and their knees are vital to getting proper bias all the time right? You dont only brake at threshold braking do you? When trail braking at less than full possible decel rates you have less weight transfer to the front and need more rear brake pressure, hence that knee that a lot of people seem to view as evil in prop valves is vital and the whole reason you want to use on in conjunction with a balance bar. You can fake your spreadsheet into working like it covers prop valves by just running it twice, once the bar set at 50/50 (or whatever it would be set to if you're running one) at your trail braking decel rate and then again at full decel rate and the balance bar setting set to include the prop valve's effect. Ultimately the prop valve isnt the best system for this because the knee doesnt totally accurately follow the braking forces you need which is where EBD comes into its own if there was a programmable one available. And if your credentials list was in any way as impressive as you make it out to be I wouldnt need to explain it to you since its basic pysics and engineering concepts that I would expect any top level team to already understand and utilize.
I'm well aware of what it does. i'm still waiting on your list.

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I'll get some corner weights for you.

Leafy seems to get the same response on some other forums as well. Take him with a grain of salt.
I understand, it's just insanely annoying to me. The community has the ability to talk to someone in the motorsports industry, and he clearly isn't. Six shooter, you're right i'll just ignore it..
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Old 10-27-2014, 09:51 AM   #66
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I forgot that you're not on the white list with the department of knowledge entropy prevention.
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Old 10-27-2014, 11:15 AM   #67
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@OGRacing You seem extremely knowledgeable about braking systems. I have a 99 Miata with presumably stock everything in the braking department. My car is 95% street car used for weekend aggressive driving fun and might make 1-2 trips to the track per year. Will be doing replacement rotors and checking/cleaning/replacing all brake hardware on the car. Can you make a pad recommendation for this vehicle? Will be sitting on 205/50 tires UHP summer tires probably Bridgestone Potenza RE-11's Whats a good pad pad for basically a street car that is driven hard? I am not concerned about dusting or noise/wear life as its a weekend only car and wont see a lot of miles. After reading these first 4 pages and looking at the 4 bajilion brake pad offerings for my car I have no idea what to get. I initially had the "more is better" thought but I see this is not true. Hawk HP+ ?
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Old 10-27-2014, 11:19 AM   #68
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.
Rotors, Find something with a curved vein, manufactured in the USA,GB,Italy or australia... if you can.
Anyone know of any "good" stock size curved vein rotors for an NB without sport brakes? The Centric brake rotors seem popular but how much could you possibly be getting for $24??
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Old 10-27-2014, 11:48 AM   #69
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Originally Posted by mxcdale View Post
@OGRacing You seem extremely knowledgeable about braking systems. I have a 99 Miata with presumably stock everything in the braking department. My car is 95% street car used for weekend aggressive driving fun and might make 1-2 trips to the track per year. Will be doing replacement rotors and checking/cleaning/replacing all brake hardware on the car. Can you make a pad recommendation for this vehicle? Will be sitting on 205/50 tires UHP summer tires probably Bridgestone Potenza RE-11's Whats a good pad pad for basically a street car that is driven hard? I am not concerned about dusting or noise/wear life as its a weekend only car and wont see a lot of miles. After reading these first 4 pages and looking at the 4 bajilion brake pad offerings for my car I have no idea what to get. I initially had the "more is better" thought but I see this is not true. Hawk HP+ ?

Mxcdale,
For a street car the HP+ is a very good offering. Ideally I would offer up the PFC Z rated Street pads. They are actually quiet, but can take up to 1400*. Unfortunately PFC doesn't offer any for the miata size. the hp+ can last till about 800*. Remember everything in a braking system is about balance. so if you're upgrading the Fronts to hp+ upgrade the rears too.

For your occasional track days I would still invest in a set of dedicated track pads. Remember that you invest a lot into your track time. Hotell, track fees, Tents, gas ect. You can easily spend $1000 bucks on a track day before you get to the track. why cance your fun on a set of pads that "should hold up". for a beginner on street tires i would go with the PFC 06 compound. the 06 is considered mid to low tQ and that will work well with your re-11's. they are also an endurance compound. so they will last 10-14% longer than a normal GT pad. that means it will cost you less in the long run vs a cheap set of race pads.

I'll include links to help you find the 06 pads.
Performance Friction 0635.06.13.44 Racing Pad - 06 Compound
Performance Friction 0636.06.13.44 Racing Pad - 06 Compound

if for whatever reason you don't like the PFC, OG racing will exchange them for padgid or hawk.

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Originally Posted by mxcdale View Post
Anyone know of any "good" stock size curved vein rotors for an NB without sport brakes? The Centric brake rotors seem popular but how much could you possibly be getting for $24??
That's going to be tough on OEM na/nb miata chassis. the existence of $30 rotors and the lack of public knowledge has flushed the higher quality rotors out of the market. We do have the higher quality rotors for the track-speed and v8 roadster kits.
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Old 10-27-2014, 12:04 PM   #70
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I like that you started the questions with "perceived". i get allot of feedback that the end result is driver error, and the driver doesn't want to listen. it's hard to tell someone they are "driving like an idiot" tactfully. i thank you for that.

Generally Powered braking systems (vacuum brake booster) are numb. without a true manual system it is very difficult to detect lock up with your foot. is that your problem? i would say maybe but i'm not 100% sure. it might be a result of incorrect pads. anser me a few more questions, What kind events are you doing, what kind of tires (age, brand, model), and how much does the car weigh (ish)? also tell me about when you are getting lock up. go threw the turn in your mind from start of the braking zone, to track in, apex, and track out... FYI if you're having braking problem @track out it's because you're spinning out of control..
I'm always more willing to blame myself than the car for a lack of speed.

Anyway, you're right in that I still have the vacuum assist. I run TT events only (no street driving), mostly on Hoosier R6s of varying age (usually between 7-18 heat cycles). The problem gets much worse with Hoosiers that have >15 heat cycles, but I assume this is more a result of the tire being basically done at that point.

Lock-up always starts in the first third of the braking zone. This is only an issue in heavy braking zones, and never an issue after corner entry (off the brakes by then).

Would adding a brace to the MC or bleeding the system more frequently improve pedal feel? Or switch pads like you mentioned? Or do I just need to man up and ditch the brake booster?

Thanks for the help!
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Old 10-27-2014, 12:22 PM   #71
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I forgot that you're not on the white list with the department of knowledge entropy prevention.
Go cry about it.
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Old 10-27-2014, 12:28 PM   #72
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That's going to be tough on OEM na/nb miata chassis. the existence of $30 rotors and the lack of public knowledge has flushed the higher quality rotors out of the market. We do have the higher quality rotors for the track-speed and v8 roadster kits.
Thanks for your help! I also will be doing a brake fluid flush with ATE fluid and possibly get a proportioning valve also. From what I have read the Miata brakes are very heavy front bias from the factory. I haven't really had a chance to drive the car much because it has crappy tires now and will be going under the knife over the winter so I am hoping to do a few mods/upgrades to the braking system overall.

I did a little searching and found that Napa carries front and rear Brembo rotors for the Miata Front part number ATM 0941347 $39.20 each and rear ATM 0941337 $36.12 each. I have a commercial account through Napa so I get these a little cheaper than over the counter. I know absolutely nothing about these other than they are Brembo brand. They just look like stock replacements not drilled or slotted. Any ideas?
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Old 10-27-2014, 02:06 PM   #73
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Originally Posted by Nate99 View Post
I'm always more willing to blame myself than the car for a lack of speed.

Anyway, you're right in that I still have the vacuum assist. I run TT events only (no street driving), mostly on Hoosier R6s of varying age (usually between 7-18 heat cycles). The problem gets much worse with Hoosiers that have >15 heat cycles, but I assume this is more a result of the tire being basically done at that point.

Lock-up always starts in the first third of the braking zone. This is only an issue in heavy braking zones, and never an issue after corner entry (off the brakes by then).

Would adding a brace to the MC or bleeding the system more frequently improve pedal feel? Or switch pads like you mentioned? Or do I just need to man up and ditch the brake booster?

Thanks for the help!


judging off what you told me your car seems to have an imbalance in the chassi set up. At this point i'm avoiding the "feel" issue because we have a lock up problem. If we solve the locking up issue, the feel will get better.

some things to check.
if you have adjustable shocks the Front Bound or Bump might be adjusted too firmly. it's rare to see shocks fail and they become harder. if the shocks are a non adjustable type, then i would look to the brakes. Do check front hubs for lateral runout. a rotor that doesn't turn true is an easy source for problems and will act finikley. Put a dial indicator on the rotor. We should see somewhere less than .003" of runout. more then that? clean the surface area of the hub and try again, clean it with sandpaper and wd40. If that checks out i would see if the OEM Prop valve is stuck. i have no idea how to test for that though. anytime i see an oem prop valve throw it away and replace it with the willwood one FM sells. if all of that checks out i would like to see more TQ in the rear of the car. ideally upgrading Hydraulic advantage is the best way, next is larger rotor size, followed by changing compounds. on Spec miata cars we are limited to only pad compound to adjust for TQ. i would look to the prop valve first from FM to solve the issue. after that i would like to see the car running a PFC 01 compound. many of my nascar teams will run the 01 because the drivers report a better feel. a miata is not a Cup car by any stretch of the imagination. The characteristics of the compounds are similar.

Ditching the booster in a Track car is never a bad idea. take your car over to a shop that does corner balancing, and have them give you your center of gravity. i'll need that number to recommend MC sizes. FYI Dual MC system is a lot of fab work to install properly.
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Old 10-27-2014, 02:14 PM   #74
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Originally Posted by mxcdale View Post
Thanks for your help! I also will be doing a brake fluid flush with ATE fluid and possibly get a proportioning valve also. From what I have read the Miata brakes are very heavy front bias from the factory. I haven't really had a chance to drive the car much because it has crappy tires now and will be going under the knife over the winter so I am hoping to do a few mods/upgrades to the braking system overall.

I did a little searching and found that Napa carries front and rear Brembo rotors for the Miata Front part number ATM 0941347 $39.20 each and rear ATM 0941337 $36.12 each. I have a commercial account through Napa so I get these a little cheaper than over the counter. I know absolutely nothing about these other than they are Brembo brand. They just look like stock replacements not drilled or slotted. Any ideas?
Anytime mxcdale,


ATE Gold Type 200 Brake Fluid

we keep ATE in stock, when you order pads don't forget the fluid. I have had 0 experience with the napa brembo rotors. when you get a set see how they are balanced, if the veins are curved, and what's the country of manufacture. Beremo is a company like any other, if they can cash in on slapping the brembo name on a chinese rotor they will.
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Old 10-27-2014, 02:23 PM   #75
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guys when you get new rotors, go thru the process of cleaning the Surface rust off the hubs. A little bit of surface rust can create a lot of lateral run out and pulsations. Plus it will ruin your brand new rotors. i send this video to people that buy the PFC-911,GT3/turbo rotors at $900 a piece.
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Old 10-27-2014, 03:55 PM   #76
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Im learning a hell of a lot, OGRacing, thanks for posting.

I dont really have a specific question, but would love to hear what you have to say about ABS.
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Old 10-27-2014, 04:23 PM   #77
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Im learning a hell of a lot, OGRacing, thanks for posting.

I dont really have a specific question, but would love to hear what you have to say about ABS.
Bosch ABS has the industry by the Nuts. the system costs 10,000. to get it tuned you need to fly an engineer from germany, to a track that you rented for the day. while he is there he will only tune 2 channels of the 18 available. it's a huge expense. but without it you're completely lost.

OEM abs is 10x slower than the Bosch unit. it's not made for motorsport. it's made for your grandma to not run into parked cars when it's snowing. because it's so slow it presents the pads with an On-Off motion. imagine a rotor at thermal capacity. Then hammering the brakes on and off 60 times a second.


not think of an OEM abs unit slapping that on-of-on-off. what do you think is going to happen?

I've seen everything fail with the use of an oem abs units/ i've seen calipers get stuck, rotors explode, pads delaminate, and ect ect..

If you got it use it when it's raining, and temps are low. other then that turn it off for dry events.
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Old 10-27-2014, 04:50 PM   #78
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And there is not only one OEM ABS, some are the source of anecdotes (1Hz units from the 80's) and some are not terrible (but not as fast as the Motorsport units).

For the miata I have experience with NB and NB2 (with EBD), both work better than "they should", but you eat a bit more pad and get a little more heat.
My reason for not turning it off in the dry is that I need the rescue when the talent runs out.
Running 6+hours means the longevity of the brake system is much more important than doing 5 hours of sprints per year.
Giving advice without knowing the specific case will be generic. Some issues can be manageable in certain cases.

Then we have the cases when you make a bumblebee fly (XP20 on 255mm OEM disks + NB ABS working well for 4h) . The cost is pad life, which is manageable is you only run 15 min at the time.
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Old 10-27-2014, 04:53 PM   #79
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And there is not only one OEM ABS, some are the source of anecdotes (1Hz units from the 80's) and some are not terrible (but not as fast as the Motorsport units).

For the miata I have experience with NB and NB2 (with EBD), both work better than "they should", but you eat a bit more pad and get a little more heat.
My reason for not turning it off in the dry is that I need the rescue when the talent runs out.
Running 6+hours means the longevity of the brake system is much more important than doing 5 hours of sprints per year.
Giving advice without knowing the specific case will be generic. Some issues can be manageable in certain cases.

Then we have the cases when you make a bumblebee fly (XP20 on 255mm OEM disks + NB ABS working well for 4h) . The cost is pad life, which is manageable is you only run 15 min at the time.

ughh what?
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Old 10-27-2014, 05:04 PM   #80
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OEM ABS failure.


OEM ABS failure
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