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Rear brakes - balancing large fronts

Old 03-13-2011, 10:08 PM
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Default Rear brakes - balancing large fronts

Starting a new thread here so we don't jam up Sav's thread with this stuff.

So I've been on the hunt for Sport rears (among other Sport brake components) for my 1.6 car. I see recommendations for the M-Tuned bracket kit (to allow use of the Sport rotors with 1.8 calipers), but I want to find the bracket for Sport rotors for two reasons:

1 - I want the Sport's larger piston
2 - 1.6l car, I'd have to source calipers anyway (might as well get what I'm after, right?)

I'm assuming I can simply get the calipers from most auto parts stores, same with the Sport BMC and possibly booster. So I suppose it's finding the bracket which is holding me up. I've emailed sites like Planet Miata and my emails have gone unanswered.

Any leads?
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Old 03-13-2011, 10:38 PM
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My local Napa carried them (caliper with carrier)
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Old 03-13-2011, 10:43 PM
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There are no brackets??

the sport brake caliper is offset to fit a ~10.75" brake rotor.

I found this out the hard way (which ultimately saved Braineack's ***)....

1. car came as a base model with teenie 01 rear brakes
2. I upgraded to the mystery Panache v8 big brake kit that used rx7 rear calipers.
3. I sold my stock brakes, calipers and all
4. I re-upgraded to the good-win version 3 kit which got me better rotors and hats and switched back to the stock rear brakes (sport or regular + brackets)
5. I bought calipers somewhere.. realized I didn't need caliper brackets with them and returned the brackets.
6. I bought brake pads "for my car" and they didn't fit but I held onto them for some reason.
7. today, several years later, brainy came over to figure out his crazy rear brake wear and noise problem. turns out his pad backplate got stuck in the caliper and the piston bent the pad and backplate all crazy. he needed stock non-sport pads. I had both sport and non sport. (sport are quite a bit more surface area fwiw).
8. he has brakes and didn't have to drive a no-brakes car somewhere to get pads.

so... yeah the sport rear caliper is offset the same as the spacer bracket already.

http://forum.miata.net/vb/showthread.php?p=4508004
look at post 74:
http://forum.miata.net/vb/showpost.p...7&postcount=74

you can kind of see how the sport brakes mounting holes are further from the center of the piston. the slider brackets also fit the larger pads.

if you buy the sport/msm calipers, you should get the whole assembly.

sadly though, raybestos and beck arnley dont list them.
autozone carries the duralast ones but they're $76 plus a 60 dollar core.
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Old 03-13-2011, 10:47 PM
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dgmorr, what was NAPA's price?

Most vendors I've found know these are sought after & rape you.
Best I've seen is $470 + S/H for a new pair.

http://www.r1concepts.com/mazda-miat...liperwheel.htm

http://www.r1concepts.com/PartImage/14145518.jpg

Last edited by Import Al; 03-14-2011 at 12:31 PM. Reason: + shipping BRO
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Old 03-13-2011, 11:10 PM
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Koto, I think you can use your 1.6 calipers with the sport rotors and m-tuned's bracket. Same way we can use our 1.6 calipers with 1.8 brackets to use the larger 1.8 rotors.

Why the lust for the larger piston?
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Old 03-13-2011, 11:30 PM
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Originally Posted by y8s
There are no brackets??

the sport brake caliper is offset to fit a ~10.75" brake rotor.
Huh... thanks a lot for that, I do see how the mounting holes are offset, interesting. So then what I'd need are the standard 94-97/1.8 brackets for the rear? Or am I assuming, once more, that there's a bracket exchange involved (mine's a '93)?

So then if there is no "Sport" bracket, my shopping list would be:

Sport calipers/pads
Sport rotors
1.8 brackets
Sport lines? (Different from 1.6 somehow? Am I assuming again?)
Wilwood adj. prop. valve
Optional: Sport BMC/booster/underhood lines
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Old 03-13-2011, 11:41 PM
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Originally Posted by curly
Koto, I think you can use your 1.6 calipers with the sport rotors and m-tuned's bracket. Same way we can use our 1.6 calipers with 1.8 brackets to use the larger 1.8 rotors.

Why the lust for the larger piston?
Based on advice from Andrew: "The sport calipers are a bit bigger and will give more rear bias to start."

He's never steered me wrong. He mentioned using stock calipers as well, but agrees that the Sport caliper is a more ideal solution.
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Old 03-13-2011, 11:46 PM
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calipers come with the brackets... these are the things that you clip the pads into and have sliders and mounting holes. they bolt to the rear hub holes.

I'm not sure about lines.

I don't think you need to do anything under the hood. (except prop valve if you want)

so your list might just be

sport calipers
sport rotors
sport pads

and then check the lines.

I'm sure someone on miata.net has laid it all out.
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Old 03-13-2011, 11:56 PM
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FWIW sport rear brackets brandie new cost 65 bucks apiece from MazdaSpeed.

Compared to 1.8 "normal" rears, Sport Rears add about 30% more rear braking action.

About 1/3 of that change comes from the increased leverage from the greater radius of the larger rotors.

About 2/3rds comes from the larger piston squeezing harder, like Hustler's Mom.
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Old 03-14-2011, 12:18 AM
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Awesome, I should have started this thread some time ago, thanks. Good info all around.

y8s - Yeah I don't need to do anything under the hood (except the prop valve) but there're a lot of posters in the dotnet thread you linked who go to bigger BMCs. I might see how I like the stock BMC with the TSE fronts and Sport rears.. but I'm anticipating a lot of pedal travel from the swap.

Last edited by kotomile; 03-14-2011 at 05:00 AM.
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Old 03-14-2011, 08:36 AM
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Koto, the single caliper I bought was $150 CDN. I have a used passenger rear sport caliper with a stuck bleed screw. There was an $80 CDN core charge in lieu of returning my used one. If you put $80 in my hands it is yours.
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Old 03-14-2011, 08:47 AM
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I just upgraded to the rear M-tuned upgrade. So stock 1.8L calipers with the 10.9" rear sport rotors. I already had the 11" front rotor upgrade and this significantly improved the balance, I'm a happy camper now.
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Old 03-14-2011, 11:19 AM
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Originally Posted by kotomile
Awesome, I should have started this thread some time ago, thanks. Good info all around.

y8s - Yeah I don't need to do anything under the hood (except the prop valve) but there're a lot of posters in the dotnet thread you linked who go to bigger BMCs. I might see how I like the stock BMC with the TSE fronts and Sport rears.. but I'm anticipating a lot of pedal travel from the swap.
I went from base 01 brakes to wilwoods + sport rears and my pedal travel is jim dandy.
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Old 03-14-2011, 10:07 PM
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Hmm, cool. I'll give it a shot.

Got a possible lead on some Sport rears from a PM.
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Old 03-15-2011, 12:00 AM
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So do we know for sure if 1.6 rear calipers will work with 1.8 brackets, mtuned's bracket, and the 10.9" rotor?
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Old 03-15-2011, 08:29 AM
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Originally Posted by curly
So do we know for sure if 1.6 rear calipers will work with 1.8 brackets, mtuned's bracket, and the 10.9" rotor?
that's what I'm using.
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Old 03-15-2011, 08:55 AM
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Originally Posted by Braineack
that's what I'm using.
Ah, good. You can understand why I thought you had changed calipers:

Originally Posted by Braineack
So stock 1.8L calipers with the 10.9" rear sport rotors
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Old 03-15-2011, 09:01 AM
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whoops. Well they are the same thing. I meant to say brackets.

But yeah, 1.6L car: 1.8L caliper brackets, 1.6L calipers, M-tuned Bracket, 10.9" Sport rotors.
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Old 03-15-2011, 10:43 AM
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I got a 4-wheel MSM setup from Tom @ PartsGroup. The MSM rear calipers are larger than standard 1.8 calipers. It was a significant improvement over standard 1.8 brakes. The F/R balance is substantially better than the stock 99 setup, and I have no pedal problems with the standard NB master.

I have read that the MSM/sport lines are somehow different than standard lines, but when I did the swap I couldn't see what the difference was. I went ahead and used the new lines because they were new, but I could have used the original lines if I had to.
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Old 03-15-2011, 11:12 AM
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Looks like 1" 929 master cylinder with the Sport Non Abs low boost assist vacuum booster and Sport calipers would balance out the front BBK the best after some reading. Maybe add a MC brace if you want stiffer brake pedal feel?

Found some info regarding 929 MC installation:

http://robrobinette.com/mastercylinder929.htm
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