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Brakes ????

Old 10-05-2015, 07:46 PM
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Originally Posted by ThePass
(depends on power/tires/aero)
I have 2/3 of these things, yes. What I need is to find the skill to use them appropriately.
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Old 10-05-2015, 07:51 PM
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Originally Posted by ThePass
Brakes? Don't brake for 5

(depends on power/tires/aero/testicular fortitude)
FTFY

Do you also not brake for 6?
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Old 10-05-2015, 07:53 PM
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Originally Posted by ThePass
Brakes? Don't brake for 5

(depends on power/tires/aero)
This is miataturbo.net, not if-you-cant-go-fast-with-90hp-you-cant-go-fast-with-900hp.miata.net.

With 300 at the wheels in my car (porky at 2650 pounds with driver, 225 RRs, no aero) I can safely say that there's no way I can take turn 5 flat. The data logger says I was hitting 112mph before braking there.

(edit) Did you mean turn 6? That's closer to reality, but I'm still doing 100+ into that corner.

--Ian
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Old 10-05-2015, 08:12 PM
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I usually tap the brakes for 6 to set the car, then its all power through the apex and up the hill. Tires just grip and grip and grip. My entry speed is not nearly as fast as Ian though
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Old 10-05-2015, 09:49 PM
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I had to do a lot more than tap, and I was sliding the car until the compression made it regain grip. Fastest I could do was 68mph before I decided to back off a little. That wall didn't look soft.
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Old 10-05-2015, 11:07 PM
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Hah, actually I lapsed and was thinking of 6.
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Old 10-05-2015, 11:08 PM
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Ok, that makes a lot more sense. I was feeling bad.
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Old 10-05-2015, 11:17 PM
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Yeah 5 is hard brakes if you have power. Creampuff may be one of the only cars that this isn't the case for (90whp, all the aero grips)
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Last edited by ThePass; 10-05-2015 at 11:35 PM.
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Old 10-10-2015, 02:20 AM
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I put multiple flat spots on my old re11a at the track like crazy running 11.75 dynalite with DTC60, sport rear with XP8 and NB sport non abs master+booster. (140whp NA no aero)

I need to add more rear brake bias I guess. I feel like I have too much brake and it's hard to modulate when braking hard.
If I brake where I used to with 1.8 calipers and DTC60/30 combo I will lock up the front tires. (I feel like I can go close to the stopping rate of the old set up but If I try to go near it, I will get a lock up)

Hopefully it's just a matter of setting rear bias because right now the car is a lock up machine.
Anyone else have a similar noob experience?
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Old 10-10-2015, 02:30 AM
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Why different pads front to back?
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Old 10-10-2015, 09:33 AM
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Originally Posted by Hungry-R
I put multiple flat spots on my old re11a at the track like crazy running 11.75 dynalite with DTC60, sport rear with XP8 and NB sport non abs master+booster. (140whp NA no aero)

I need to add more rear brake bias I guess. I feel like I have too much brake and it's hard to modulate when braking hard.
If I brake where I used to with 1.8 calipers and DTC60/30 combo I will lock up the front tires. (I feel like I can go close to the stopping rate of the old set up but If I try to go near it, I will get a lock up)

Hopefully it's just a matter of setting rear bias because right now the car is a lock up machine.
Anyone else have a similar noob experience?
Hawk came out with a less agressive DTC 50 or maybe even the 30's up front. Or try Cobalt XR3 or PFC11, which both should have less initial bite than the DTC60.
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Old 10-10-2015, 03:03 PM
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Originally Posted by Hungry-R
I put multiple flat spots on my old re11a at the track like crazy running 11.75 dynalite with DTC60, sport rear with XP8 and NB sport non abs master+booster. (140whp NA no aero)

I need to add more rear brake bias I guess. I feel like I have too much brake and it's hard to modulate when braking hard.
Step 1: Stop running mix-matched pads from different brands front to rear.

So many variables are different between brands. Torque rise in relation to temperature, initial bite, latent friction (how much "stick" the pad has as you ease off the pedal), etc. etc. etc. Running pads from two different brands is a recipe for a nightmare 99/100 times.

Anectodal evidence: First time I tried PFC pads (which are much awesome sauce), I just put 01's in the front and left my DTC60's in the rear. I was stuck on that failboat for the whole weekend. The PFC's had such a smoother initial bite and release that the brakes would completely change characteristics depending on where in the pedal travel I was. I couldn't trail brake without risk of snap-oversteer. Now I run PFC 01 front, PFC 11 rear and it's a dream. I could easily see someone trying an otherwise great pad only on one side of the car, having a terrible time as a result, and incorrectly blaming the pads, the hardware bias, etc. etc.

Side-note though: you should really have a prop valve
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Old 10-11-2015, 06:58 PM
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Originally Posted by ThePass
Step 1: Stop running mix-matched pads from different brands front to rear.

So many variables are different between brands. Torque rise in relation to temperature, initial bite, latent friction (how much "stick" the pad has as you ease off the pedal), etc. etc. etc. Running pads from two different brands is a recipe for a nightmare 99/100 times.

Anectodal evidence: First time I tried PFC pads (which are much awesome sauce), I just put 01's in the front and left my DTC60's in the rear. I was stuck on that failboat for the whole weekend. The PFC's had such a smoother initial bite and release that the brakes would completely change characteristics depending on where in the pedal travel I was. I couldn't trail brake without risk of snap-oversteer. Now I run PFC 01 front, PFC 11 rear and it's a dream. I could easily see someone trying an otherwise great pad only on one side of the car, having a terrible time as a result, and incorrectly blaming the pads, the hardware bias, etc. etc.

Side-note though: you should really have a prop valve
I have prop valve installed already. so should i get xp8 or xp10 front pads?
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Old 10-11-2015, 11:58 PM
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Originally Posted by Hungry-R
I put multiple flat spots on my old re11a at the track like crazy running 11.75 dynalite with DTC60, sport rear with XP8 and NB sport non abs master+booster. (140whp NA no aero)

I need to add more rear brake bias I guess. I feel like I have too much brake and it's hard to modulate when braking hard.
If I brake where I used to with 1.8 calipers and DTC60/30 combo I will lock up the front tires. (I feel like I can go close to the stopping rate of the old set up but If I try to go near it, I will get a lock up)

Hopefully it's just a matter of setting rear bias because right now the car is a lock up machine.
Anyone else have a similar noob experience?
I disagree with the above posters. You simply have way too much pad and rotors for those tires. Minus the mismatched pads, your setup would be optimized for 200+ whp and Hoosiers. You're on old Street tires with TTE power? Swap in some HP+ or something. Or get real tires...

Awesome brakes aren't going to make shitty tires work better.
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Old 10-12-2015, 09:06 AM
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Originally Posted by dasting
I disagree with the above posters. You simply have way too much pad and rotors for those tires. Minus the mismatched pads, your setup would be optimized for 200+ whp and Hoosiers. You're on old Street tires with TTE power? Swap in some HP+ or something. Or get real tires...

Awesome brakes aren't going to make shitty tires work better.
This.

I'm running XP8's all around on stock 99 rotors, prop valve, no abs and I still have problems locking up my fresh 225 RS3s. I couldn't imagine running giant rotors and aggressive pads on street tires. I'm sure 90% of it is my lack of talent, but still...
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Old 10-12-2015, 12:57 PM
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Originally Posted by dasting
I disagree with the above posters. You simply have way too much pad and rotors for those tires. Minus the mismatched pads, your setup would be optimized for 200+ whp and Hoosiers. You're on old Street tires with TTE power? Swap in some HP+ or something. Or get real tires...

Awesome brakes aren't going to make shitty tires work better.
ehhh stay away from the hp+ for race tracks. they will work for a little bit, but the max temp isn't that great for track events.
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Hopefully so, but let's hope it's never necessary. Experiencing your safety gear in action is ... not optimal.
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Old 10-12-2015, 01:09 PM
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Originally Posted by OGRacing
ehhh stay away from the hp+ for race tracks. they will work for a little bit, but the max temp isn't that great for track events.
*insert your favorite dual Street/track duty pad here*

I was just making a point. 11.75" rotors with dtc60s and old, 3 generation ago 200tw tires does not compute.
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Old 10-12-2015, 05:14 PM
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Originally Posted by dasting
*insert your favorite dual Street/track duty pad here*

I was just making a point. 11.75" rotors with dtc60s and old, 3 generation ago 200tw tires does not compute.
Huh? Old tires means less grip, lower cornering speeds, but that probably means more braking, not less. Yes, you'll need to use less pressure to avoid locking them up, but big rotors and DTC-60s are about temperature, not about peak braking gees.

--Ian
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Old 10-12-2015, 06:41 PM
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DTC 60 seem to be a bit too much pad for a mild Miata. They are listed as high torque pads.

DTC-60 400-1600°F; 204-871°C NASCAR/NASCAR Modified Sports Car/GT/GS/
Letter Code G High Temp & High Torque Hooters Cup All Club Levels
Provides Superior Pad and Disc Wear ARCA Open Wheel/Formula
Excellent Torque Control ASA Monster Trucks
Excellent Modulation and Super Late Models CORR Pro2/Pro4
Release Characteristics Pavement Street Stock
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Old 10-12-2015, 08:19 PM
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Originally Posted by codrus
Huh? Old tires means less grip, lower cornering speeds, but that probably means more braking, not less. Yes, you'll need to use less pressure to avoid locking them up, but big rotors and DTC-60s are about temperature, not about peak braking gees.

--Ian
No.

Massive rotors (applying more torque) and dtc60 pads (extremely high mu, meaning more torque) means you're putting a lot more torque (funny how that works) on slowing down the wheel than with smaller rotors and less aggressive pads. This locks up wheels easier. R7s resist lock up better than old crappy street tires.

Yes, the rotors are better at dissipating heat, and the pads are better at operating at a high heat.
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