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Old 01-25-2016, 02:13 PM
  #681  
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Originally Posted by Savington
Yeah. Why doesn't PFC make a proper speed-clip compatible Dynapro pad in 12mm thickness?
I've bugged them many times. right now they are producing a crap ton of pads, calipers and rotors for Porsche. if you go to a imsa race you will see every Porsche with full pfc kit. so cool, but that means they are slamming right now. I got those pads and the c6z06 pads on the wish list.
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Originally Posted by Mobius
Hopefully so, but let's hope it's never necessary. Experiencing your safety gear in action is ... not optimal.
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Old 01-25-2016, 05:39 PM
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Hey Johnny! I ordered some brake fluid from you.

Too bad its stuck in Virginia in the SNOWPOCALYPSE!
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Old 01-26-2016, 01:56 PM
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Originally Posted by Oh4One4
Hey Johnny! I ordered some brake fluid from you.

Too bad its stuck in Virginia in the SNOWPOCALYPSE!
Thank you We appreciate you!
the OG Racing FB page has constant updates of how terrible our parking lot is lol. yesterday we had 2 guys that couldn't leave their subdivision.
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Originally Posted by Mobius
Hopefully so, but let's hope it's never necessary. Experiencing your safety gear in action is ... not optimal.
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Old 02-22-2016, 10:56 PM
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Rust.

My brand new rotors have sat long enough that they have become encrusted with rust. Brand new pads. What do I do now? Once broken in, what do I do? Virginia atmosphere likes to make rust; in like three days during the summer.
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Old 02-23-2016, 11:11 AM
  #685  
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I don't know how bad yours are, but whenever I've had rust-encrusted rotors, including my brother's Integra which sat outside uncovered with parking brake on for weeks (months?) on end, the solution was just to drive the car and use the brakes. Terrible noises and vibrations ensued and then subsided until life was good again.
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Old 02-23-2016, 11:15 AM
  #686  
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Originally Posted by TalkingPie
I don't know how bad yours are, but whenever I've had rust-encrusted rotors, including my brother's Integra which sat outside uncovered with parking brake on for weeks (months?) on end, the solution was just to drive the car and use the brakes. Terrible noises and vibrations ensued and then subsided until life was good again.
+1

Just run them. If the pads are still good and it's not large amounts of crust just surface rust you'll be good. Mine sat outside of BEGi for many months in the rain & sun. Few hard braking stops and I was good. Plus the outside kitties protected my car from mice and prob other animals.
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Old 02-23-2016, 12:20 PM
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I was just concerned because these pads and rotors have NOT been bedded yed. Zero transfer layer as of now.
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Old 02-23-2016, 12:22 PM
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I would just drive it.
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Old 02-23-2016, 03:23 PM
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Originally Posted by patsmx5
I would just drive it.
yep. easy way to remove transfer layer is to wash the car. let the rotors rust up, then go out and bead in the new pads
.
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Originally Posted by Mobius
Hopefully so, but let's hope it's never necessary. Experiencing your safety gear in action is ... not optimal.

Last edited by OGRacing; 02-24-2016 at 12:35 PM.
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Old 02-23-2016, 05:09 PM
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Will do. Thanks guys.
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Old 03-31-2016, 06:50 PM
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Default Moving away from Booster, moving to dual master pedal box

This thread has been a great read..!

Question concerning deleting the brake booster and moving to a dual master cylinder/balance-bar setup:

This Miata is strictly track driven, not street legal.
2400 pound race-weight, likely to decrease down to 2350, wet, including driver.
50.5/49.5 weight balance
Mild/mediocre front/rear aero (air dam/splitter, fastback, GT-200 wing)
1.9L long-rod engine with individual throttles, 8500 redline, bumpy cams, and not a lot of vacuum in the intake manifold.
Legit ~200hp @ the wheels N/A, (pump gas! Anyway...)
Stock pedal box
Sport non-ABS booster
15/16" master
Wilwood proportioning valve
DynaPro radial mount calipers & V8R hats/curved-vented 11.75" rotors, Front
Stock calipers & 10.9" Sport rotors, Rear, disabled parking brake
Cobalt Friction XP2/XP3 F/R pads
3" brake cooling ducts, front

I record a fair amount of data, including front/rear brake line pressure. In heavy braking zones, front brake line pressure maxes out at about 950psi, and rear at 800psi. The car is good for -1.4 g's in braking zones (average sustained braking is ~-1.3g). The foot/leg/pedal effort is acceptable.

The pedal feels inconsistent, and my suspicion is that the factory booster contributes heavily to this problem. I doubt it is getting consistent vacuum from the engine. I can always generate 'enough' brake force, but the amount of pedal travel and required effort seem to vary. This is during initial application as well as sometimes deep into the braking zone. I have dismissed (some) of the initial inconsistency to pad knock-back (at certain tracks). Tracks I visit include Watkins Glen, Summit Point (main), NHMS, Palmer Motorsports Park, Mt. Tremblant, Mosport / Canadian Tire, etc., so big-boy tracks as well as some tight and technical.

My question is concerning the brake booster, and moving away from it, and toward a wilwood/tilton pedal box with dual masters.

The goal is to improve pedal feel and consistency. Bonus points for slightly reducing pedal travel without increasing leg force. Bonus, bonus points for ridding my car of the flimsy stock pedal box. The car is certainly drive-able, fast, and fun, but I have been dealing with or driving around my unhappyness with the brake performance/feel for a few seasons now.

Given the above, where to start with front/rear master cylinder sizes, and pedal ratio? I did all of the brake math long ago to create my own radial mount setup, only to find bbundy's Mini write-up, then designed my own rotor hats to work with them, only to find V8R release their hats/kit just before I sent my files for production. So I appear to be a master of doing the manual work, only to find that someone else has done it or is just about to release a product. I figure before I hurt my brain with all that math again, I'd ask a professional.

From research (and a bit of experience), I expect that a proportioning valve will still be helpful for fine tuning the rear (lockup), yes?

Is OG still at Summit Point? I love that track and have been a customer many times. Won a 13-hour there in my then-ITA Miata about a decade ago. Among the few tracks in the Northeast where you can visit a good parts shop and pickup swag, too. The trip to Summit Point was one of the highlights of many seasons, when my local club would travel south to Summit to kick off our season in warmer-than-New England weather. Oh, but that damned red clay/soil. I think I still have some stuck under the car somewhere.

Thanks,

Will
Attached Thumbnails Anyone have any brake questions?-palmer_brake_pressure.jpg  
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Old 04-01-2016, 01:07 AM
  #692  
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Default Anyone have any brake questions?

Electric vacuum pump?
I've been thinking about it for my own setup but have not started to dumpster dive after one with simple connection and internal regulation.

Smaller change and smaller headaches, but maybe too small return.
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Old 04-01-2016, 01:53 AM
  #693  
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Hydroboost!

I dunno, I've driven a few non-power-assisted brake cars, but they weighed substantially less than a ton. I don't think I'd want to try it on a Miata.

--Ian
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Old 04-01-2016, 01:57 AM
  #694  
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I drove a few trucks without power brakes when searching for my truck. I didn't mind the non power brakes. It was the lack of power steering that killed it for me.

Those were 4 wheel drums though....
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Old 04-01-2016, 02:19 AM
  #695  
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Originally Posted by aidandj
I drove a few trucks without power brakes when searching for my truck. I didn't mind the non power brakes. It was the lack of power steering that killed it for me.

Those were 4 wheel drums though....
Drums are self-energizing, that makes a huge difference.

--Ian
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Old 04-01-2016, 10:14 AM
  #696  
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Originally Posted by codrus
Hydroboost!

I dunno, I've driven a few non-power-assisted brake cars, but they weighed substantially less than a ton. I don't think I'd want to try it on a Miata.

--Ian
hahah we used to sponsor Pro-touring .com I received so many questions about hydro-boost systems. and other insane questions that i decided i couldn't help anyone and gave up talking. hydro boosts are nuts they have no modulation it's nothing or 900 lbs of force. they did work fine on the hummers i worked on back in the old army days.
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Originally Posted by Mobius
Hopefully so, but let's hope it's never necessary. Experiencing your safety gear in action is ... not optimal.
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Old 04-01-2016, 10:24 AM
  #697  
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Originally Posted by wildo
This thread has been a great read..!

Question concerning deleting the brake booster and moving to a dual master cylinder/balance-bar setup:

This Miata is strictly track driven, not street legal.
2400 pound race-weight, likely to decrease down to 2350, wet, including driver.
50.5/49.5 weight balance
Mild/mediocre front/rear aero (air dam/splitter, fastback, GT-200 wing)
1.9L long-rod engine with individual throttles, 8500 redline, bumpy cams, and not a lot of vacuum in the intake manifold.
Legit ~200hp @ the wheels N/A, (pump gas! Anyway...)
Stock pedal box
Sport non-ABS booster
15/16" master
Wilwood proportioning valve
DynaPro radial mount calipers & V8R hats/curved-vented 11.75" rotors, Front
Stock calipers & 10.9" Sport rotors, Rear, disabled parking brake
Cobalt Friction XP2/XP3 F/R pads
3" brake cooling ducts, front

I record a fair amount of data, including front/rear brake line pressure. In heavy braking zones, front brake line pressure maxes out at about 950psi, and rear at 800psi. The car is good for -1.4 g's in braking zones (average sustained braking is ~-1.3g). The foot/leg/pedal effort is acceptable.

The pedal feels inconsistent, and my suspicion is that the factory booster contributes heavily to this problem. I doubt it is getting consistent vacuum from the engine. I can always generate 'enough' brake force, but the amount of pedal travel and required effort seem to vary. This is during initial application as well as sometimes deep into the braking zone. I have dismissed (some) of the initial inconsistency to pad knock-back (at certain tracks). Tracks I visit include Watkins Glen, Summit Point (main), NHMS, Palmer Motorsports Park, Mt. Tremblant, Mosport / Canadian Tire, etc., so big-boy tracks as well as some tight and technical.

My question is concerning the brake booster, and moving away from it, and toward a wilwood/tilton pedal box with dual masters.

The goal is to improve pedal feel and consistency. Bonus points for slightly reducing pedal travel without increasing leg force. Bonus, bonus points for ridding my car of the flimsy stock pedal box. The car is certainly drive-able, fast, and fun, but I have been dealing with or driving around my unhappyness with the brake performance/feel for a few seasons now.

Given the above, where to start with front/rear master cylinder sizes, and pedal ratio? I did all of the brake math long ago to create my own radial mount setup, only to find bbundy's Mini write-up, then designed my own rotor hats to work with them, only to find V8R release their hats/kit just before I sent my files for production. So I appear to be a master of doing the manual work, only to find that someone else has done it or is just about to release a product. I figure before I hurt my brain with all that math again, I'd ask a professional.

From research (and a bit of experience), I expect that a proportioning valve will still be helpful for fine tuning the rear (lockup), yes?

Is OG still at Summit Point? I love that track and have been a customer many times. Won a 13-hour there in my then-ITA Miata about a decade ago. Among the few tracks in the Northeast where you can visit a good parts shop and pickup swag, too. The trip to Summit Point was one of the highlights of many seasons, when my local club would travel south to Summit to kick off our season in warmer-than-New England weather. Oh, but that damned red clay/soil. I think I still have some stuck under the car somewhere.

Thanks,

Will

yep your assumptions are exactly right. The engine can't deliver vacuum under WOT (wide open throttle). Guess what you need when your done with a straight away... your booster's vacuum. dive for the middle pedal, uses the reserve vacuum, engine tries to make more vacuum. the whole time you feel this fight in your foot. i personally am under going a huge makeover and replacing the booster with dual tilton mc setup. this without a doubt will require more effort, so if you want to do the same start doing squats now. you'll need about 125-150lbs of pressure as before you only needed 90.


I went with a 13/16 and 3/4 mc's. but i have 11.75" rotors out back, afco F33 calipers on all 4, with 1.75" pistons F and 1.38" pistons R.

i can size your mc just shot me everything. i need to know your caliper piston sizes, rotor size, pad swept area, and what pedal box your want to go with.
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Originally Posted by Mobius
Hopefully so, but let's hope it's never necessary. Experiencing your safety gear in action is ... not optimal.
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Old 04-01-2016, 11:44 AM
  #698  
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Or use a vacuum storage reservoir like people with big cams have been doing since the 1960s. Essentially an empty can teed into the vacuum booster line on the booster side of the check valve. It will store additional vacuum if your engine makes very little of it.
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Old 04-01-2016, 12:17 PM
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Originally Posted by sixshooter
Or use a vacuum storage reservoir like people with big cams have been doing since the 1960s. Essentially an empty can teed into the vacuum booster line on the booster side of the check valve. It will store additional vacuum if your engine makes very little of it.
pedal box is lighter
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Originally Posted by Mobius
Hopefully so, but let's hope it's never necessary. Experiencing your safety gear in action is ... not optimal.
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Old 04-01-2016, 12:20 PM
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Than an empty coffee can?
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