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Old 08-16-2016, 02:42 PM
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Originally Posted by joshbot007
I got one. So I really want to upgrade my breaks to help with the power that will be coming from the turbo. I have rpf1 15x7 wheels and was told that I can not fit a big break kit with these wheels. I was OK with this at the time of purchase but now that I want bigger breaks I'm kind of in a struggle. So I guess what I'm asking is that without going to a big break kit what is the best or most reasonable break setup (including calipers and breaks if need be) that I can jam (doesn't have to be jammed it could be stock size i'm just trying to achieve good breaking power) in underneath these wheels that will give me sufficient breaking for a 250 whp car.
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Old 08-16-2016, 03:18 PM
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Originally Posted by Chilicharger665
What are "breaks?"
Its what government workers do all day.
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Old 08-16-2016, 06:41 PM
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Haha I guess that is what I get for writing a quick post and not checking myself lol. Thank you for you advice!
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Old 08-22-2016, 03:23 PM
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Procrastinator deluxe, these have been sitting on the shelf since the winter and before that I waited abut three years before ordering...
Dynapro radial not perfectly shimmed
How far out should I shim the caliper? In the picture I have not used any of the wafer shims, adding two makes the disk mostly flush with the pad material edge.

What is a decent replacement for the IMO stupid crimped 12-edge lock nuts for the caliper?
Finding a 12-edge 7/16" (11mm ring wrench was a snug fit) socket here isn't an easy task.
No I have not checked the thread, mot probably something imperial ...

For other procrastinators, this task was really easy with a $8 7/16" reamer, the tapered start was enough to not need to drill first.

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Old 10-29-2016, 01:42 AM
  #885  
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hello there.
I may have a different attitude toward "big" brake kit. My car is a very track oriented, but is still driven on the road to and from trackdays... not much for anything else. It's 99' NB 10 AE. Brake system is OEM except for braided lines and pads i considered being "good" pads Ferodo DS3000 Front & DS2500 Rear (fluid RBF 600). The car is untouched power wise (so far...) even if running under MS3/Tuner Studio. On Track, I don't feel like missing braking power to stop my skinny 195/50 Toyo R888 from rolling.
My issue is that the OEM pads shape are expensive compared to the Wilwood shape pads, most of the time they cost twice the wilwood's price. (same Brand/same compound)!

So I'm willing to upgrade to a Wilwood "basic" kit to lower my running cost, not primarily to increase my braking torque. I've read about the risk of over braking the car, and loose the balance i have now between my component - power/tires/brakes. So what are the risk of over braking the car with my current tire set-up?
Since I'll get bigger rotor (11'' vs 10''), is using pads with a lower torque output than my current pads -but still fit for track (ab)use- a good way to avoid over-braking?
If I invest in such a "big" kit (i get it's not so "big" compared to some...) do I also need to (must?) address the rear bias with an adjustable valve?


So far I don't need more power but in the coming future, i 'll get wider wheels/tires ( 215/225 tires on 15x8) and i have the crazy project to install a turbo... Keep this in mind.
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Old 10-29-2016, 02:52 AM
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Originally Posted by herduge
o I'm willing to upgrade to a Wilwood "basic" kit to lower my running cost, not primarily to increase my braking torque. I've read about the risk of over braking the car, and loose the balance i have now between my component - power/tires/brakes. So what are the risk of over braking the car with my current tire set-up?
Big brake kits are not primarily about increasing brake torque, the stock gear has more than enough torque to lock the tires from 100 mph, even with sticky tires on it. BBKs are primarily about increasing the ability of the braking system to cope with the heat loads imposed by use on the track, especially with higher-than-stock power cars. Larger rotors give more heat sink capacity, and have a larger surface area thus increasing the rate at which heat can be transferred to the air when not braking.

Secondary factors for a BBK are a reduction in weight due to lightweight aluminum calipers and rotor-on-hat designs, increased stiffness in the caliper to improve brake feel and reduce tapered pad wear, and yes, lower costs for consumables. Still though, you need to do a lot of track days before you pay off a thousand dollar brake kit with cheaper pads, and you have to be careful that that those savings don't vanish from needing to buy more expensive rotors (different kits use rotors with different replacement costs, but most of them are substantially higher cost than an OEM rotor).

I'm not sure what you mean by "over braking" the car. Increasing the caliper piston size without changing anything else in the system will result in a softer pedal, with less force over a longer distance to achieve the same piston clamping force. A larger diameter rotor will give you an increase in brake leverage, but the effect is fairly small (roughly 10% for going from an 10" rotor to an 11" one). Yes, you do need to be careful to keep the right front:rear balance when changing piston sizes. An adjustable prop valve is not really the right solution for this -- better is to increase the size of the rear rotors as well (say, 10.75" rear sport brakes) so that they balance the fronts.

--Ian
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Old 10-29-2016, 03:40 AM
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Originally Posted by codrus
Secondary factors for a BBK are a reduction in weight due to lightweight aluminum calipers and rotor-on-hat designs, increased stiffness in the caliper to improve brake feel and reduce tapered pad wear, and yes, lower costs for consumables. Still though, you need to do a lot of track days before you pay off a thousand dollar brake kit with cheaper pads, and you have to be careful that that those savings don't vanish from needing to buy more expensive rotors (different kits use rotors with different replacement costs, but most of them are substantially higher cost than an OEM rotor).
Loosing weight is always appreciable, more so for non-suspended weight... But it's more difficult to sell to the Family Finance Officer
I'm not so sure that the "basic" dynalite caliper are stiffer than the cast iron OEM one though. Good point regarding rotor replacement ( i may have underestimated that point to the aforementioned FFO). I was under the impression that 2 pieces rotor would last longer than the OEM rotor due to the better cooling/thermal capacity... i may be wrong.
I run trough to 2/3 sets of pads a year... that's about 450 USD a year (font). Plus my pads and discs are worn out, so a basic big kit is roughly just 500 more than a OEM replacement. It's theses 500 that i have to absorb, not 1000.

Originally Posted by codrus
I'm not sure what you mean by "over braking" the car. Increasing the caliper piston size without changing anything else in the system will result in a softer pedal, with less force over a longer distance to achieve the same piston clamping force. A larger diameter rotor will give you an increase in brake leverage, but the effect is fairly small (roughly 10% for going from an 10" rotor to an 11" one). Yes, you do need to be careful to keep the right front:rear balance when changing piston sizes. An adjustable prop valve is not really the right solution for this -- better is to increase the size of the rear rotors as well (say, 10.75" rear sport brakes) so that they balance the fronts.

--Ian
i was thinking that sending more pressure to the rear caliper would do the same?
You say than increasing the rotor size by 10% at front won't increase brake torque by much... So why to you recommend increasing rotor size at the rear for better balance over the adjustable prop valve? Am i missing something?
i could be tempted to do booth!
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Old 10-29-2016, 02:00 PM
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Originally Posted by herduge
Loosing weight is always appreciable, more so for non-suspended weight... But it's more difficult to sell to the Family Finance Officer
I'm not so sure that the "basic" dynalite caliper are stiffer than the cast iron OEM one though. Good point regarding rotor replacement ( i may have underestimated that point to the aforementioned FFO). I was under the impression that 2 pieces rotor would last longer than the OEM rotor due to the better cooling/thermal capacity... i may be wrong.
I run trough to 2/3 sets of pads a year... that's about 450 USD a year (font). Plus my pads and discs are worn out, so a basic big kit is roughly just 500 more than a OEM replacement. It's theses 500 that i have to absorb, not 1000.
So I notice that it says you're in France -- I have no idea what prices there are like. Here in the US, I can get aftermarket stock-equivalent rotors for an NB for about $20 each, and OEM-shaped pads cost only 20-30% more than Wilwood-shaped ones.

Even the inexpensive Dynalites are stiffer than stock single-piston calipers and do a better job of controlling the location of the pads during repeated hard braking. Sure, they're nowhere close to something like a Porsche or AP caliper, but the OEM ones are hampered by the need to slide in and out on the slider pins.

i was thinking that sending more pressure to the rear caliper would do the same?
You say than increasing the rotor size by 10% at front won't increase brake torque by much... So why to you recommend increasing rotor size at the rear for better balance over the adjustable prop valve? Am i missing something?
i could be tempted to do booth!
Yes, sending more pressure to the rear caliper would do that, but that's not what an adjustable proportioning valve does (at least, it's more complicated than that). There's a writeup on how they work at Stoptech's site that's worth reading (alas, it appears to be down at the moment) http://stoptech.com/technical-suppor...tioning-valves Adjustable prop valves won't fix large differences in balance, they're fine-tuning tools. You want to start by matching the hardware as closely as possible and then add a prop valve if you want the last little bit.

--Ian
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Old 12-08-2016, 03:20 PM
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Guy does a pretty good job of talking about brakes. Especially for being stoned out of his mind.
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Old 12-08-2016, 09:18 PM
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I posted this on the 949 subforum, but perhaps this is a better spot.

I saw the rear brake bracket adapter kit for sale on your site: Miata Sport rear rotor Kit
This particular kit is to use sport brake rotors while retaining the rear calipers and pads. I was reading the description and it seems like it's only recommended for aftermarket brakes.

I'm swapping to sport front brakes on my nb1 and it seems that the larger rear rotors aren't recommended for these. I'm just curious what you've found that led you to this conclusion. Does having the larger rear brakes throw balance off? Since the sport brakes themselves are larger in the rear, are those more 'unbalanced' than the 1.8s?

Thanks!
Asked because I figured that upping the hpx2 on a street car required better braking. I bought sport fronts and wanted to run 1.8 rears with the brackets for bigger rotors to have better pad selection.

And this thread: https://www.miataturbo.net/suspensio...le-99-a-84151/
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Old 02-17-2017, 10:06 PM
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I have a general rotor question. I have, what I believe to be an early willwood- goodwin racing (not sure) front kit with the 11" willwood rings with 6 bolt hat design. I need new rings, but I can't seem to find the correct hardware with the rings from a miata vendor. I want to support the miata shops but i'm about ready to take the rotors apart and order from the first place I find with the correct hardware kit. I would like to buy the 11" directional rings, plus the bolts, washers and nuts. the hats are old but in prefect shape so I see no reason to upgrade hats at this point.. I've done this before and certainly insist on new hardware. any suggestions are welcome. I'm interested in the 949 directional 11", non slotted rings, so perhaps I need to email em or call them about hardware. I love the idea of AP rings but just don't want to spend the money this year, other stuff to fix first.

just for fun, I've heard drilled rotors, originally found on Porsche rotors, are actually cast into the rotor not drilled. drilled was adopted as a way to copy the look in the aftermarket. the Porsche cast holes are helpful shaving the pads a little, much like slotted, when the pads/ rotors get over heated, especially on pads designed for the street or older street organic pads. This is why you can safely drive on Porsche rotors that appear to have many cracks, up to a point obviously, where this is less true on aftermarket drilled rotors.

Last edited by psreynol; 02-17-2017 at 10:24 PM.
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Old 02-18-2017, 07:44 AM
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Originally Posted by psreynol
I have a general rotor question. I have, what I believe to be an early willwood- goodwin racing (not sure) front kit with the 11" willwood rings with 6 bolt hat design. I need new rings, but I can't seem to find the correct hardware with the rings from a miata vendor. I want to support the miata shops but i'm about ready to take the rotors apart and order from the first place I find with the correct hardware kit. I would like to buy the 11" directional rings, plus the bolts, washers and nuts. the hats are old but in prefect shape so I see no reason to upgrade hats at this point.. I've done this before and certainly insist on new hardware. any suggestions are welcome. I'm interested in the 949 directional 11", non slotted rings, so perhaps I need to email em or call them about hardware. I love the idea of AP rings but just don't want to spend the money this year, other stuff to fix first.

just for fun, I've heard drilled rotors, originally found on Porsche rotors, are actually cast into the rotor not drilled. drilled was adopted as a way to copy the look in the aftermarket. the Porsche cast holes are helpful shaving the pads a little, much like slotted, when the pads/ rotors get over heated, especially on pads designed for the street or older street organic pads. This is why you can safely drive on Porsche rotors that appear to have many cracks, up to a point obviously, where this is less true on aftermarket drilled rotors.
No one has ever been able to lay hands on these mythical cast in holes rotors, the was even a bounty on one road racing website I frequent, never showed up. Holes are not needed with modern pad design, they don't out gas like pads from 50 years ago. Holes just chew up pads and remove mass that could be transferring heat away from your pads. They also serve as a perfect point for cracks to form. Connect enough of the dots (literally) and you need to junk them. Smooth rotors will also form micro cracks, but without huge stress concentrators they generally last way longer before the cracks progress to the point of junking the rotors.
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Old 02-18-2017, 03:15 PM
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Originally Posted by psreynol
I have a general rotor question. I have, what I believe to be an early willwood- goodwin racing (not sure) front kit with the 11" willwood rings with 6 bolt hat design. I need new rings, but I can't seem to find the correct hardware with the rings from a miata vendor. I want to support the miata shops but i'm about ready to take the rotors apart and order from the first place I find with the correct hardware kit. I would like to buy the 11" directional rings, plus the bolts, washers and nuts. the hats are old but in prefect shape so I see no reason to upgrade hats at this point.. I've done this before and certainly insist on new hardware. any suggestions are welcome. I'm interested in the 949 directional 11", non slotted rings, so perhaps I need to email em or call them about hardware. I love the idea of AP rings but just don't want to spend the money this year, other stuff to fix first.
Do they look like this?



If so, those are version 1 (or version 2, the only difference between 1 and 2 was the rears) Goodwin rotors. They're a standard Wilwood hat, although I forget the part number. Goodwin Racing doesn't seem to have them on their web site any more (that's where I would mostly buy replacements), but if you call them up they can probably either order you some or at least give you the part # so you can order them from Summit or the like. That's assuming the rotors are still made -- the version 3 and (I think) version 4 rotor rings are no longer available. The v1/2 were a standard part out of Wilwood's catalog, though, so there's a better chance.

As far as the hardware is concerned, the bolts that Goodwin included with the kit were nothing special -- button head coarse thread bolts with split ring lock washers, normal nuts, and no provision for safety wire. When I had the kit I used aircraft bolts instead.

I don't think the hats from the v1/v2 Goodwin kit are compatible with the modern 11" rotors as used in the Wilwood, Trackspeed, or 949 kits.

--Ian
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Old 03-24-2017, 08:27 PM
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Pad question.

Brake setup: 11.75" mini Cooper rotor. Wilwood dynapros. 200hp+ track car.

I'm not happy with how fast my DTC-60s are wearing in the front. Will other types of pads last longer (PFC, carbotech, etc) or is it just something I need to accept with more power.

I'm happy with how they perform, just would like them to last longer.
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Old 03-24-2017, 08:37 PM
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Originally Posted by aidandj
Pad question.

Brake setup: 11.75" mini Cooper rotor. Wilwood dynapros. 200hp+ track car.

I'm not happy with how fast my DTC-60s are wearing in the front. Will other types of pads last longer (PFC, carbotech, etc) or is it just something I need to accept with more power.

I'm happy with how they perform, just would like them to last longer.
I presume you are already running brake ducts? Out of all the pads I've run last year I've been pretty happy with the PFC01 on my 11.75 set up and getting reasonable wear for the power I make. DTC-60s never lasted that long for me, I had issues with the pads chucking apart even with brake ducts on my old 11" set up. Another pad that didn't last long was the Porterfield R4-1s, I tore through a set in two days at Chuckwalla with my 11.75 last year.

Keep in mind there are a lot of factors when it comes to brake & tire wear rate. While power can make a substantial impact on how quickly things wear more importantly is how the driver is using the hardware. Intermediate drivers tend to stay on the brakes longer which tends to wear through the pads quicker. Likewise I went through ~33% of the tread on sticker NT-01s in two days at the track, these used to last me all year.
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Old 03-24-2017, 08:42 PM
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Yes. 2.5" ducts.
I've been wanting to try PFCs. Any idea if a PFC in front and a DTC-60 in the rear would be weird. I have basically brand new rears because they barely wear. And don't want to toss them.

If they engaged differently I could see some weird feelings. I might just give it a shot and see what happens.

At ORP pads barely wear. Lower speeds, elevation change to slow you down.

PIR is basically 2 drag races with a turn or 2 in the middle.
​​​​​
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Old 03-24-2017, 08:44 PM
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Originally Posted by aidandj
Yes. 2.5" ducts.
I've been wanting to try PFCs. Any idea if a PFC in front and a DTC-60 in the rear would be weird. I have basically brand new rears because they barely wear. And don't want to toss them.

If they engaged differently I could see some weird feelings. I might just give it a shot and see what happens.

At ORP pads barely wear. Lower speeds, elevation change to slow you down.

PIR is basically 2 drag races with a turn or 2 in the middle.
​​​​​
​​​​​​
Don't mix compounds, Ryan tried that exact combo once and the results were terrible. The DTC-60 needs a bunch of heat before they come on and the PFC almost good to go at turn one. Make sure you surface the rotors or put new ones on, mixing transfer layers is a recipe for disaster too.
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Old 03-24-2017, 08:47 PM
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Ive got a brand new set of rotors waiting to go after I finish off these dtc60s. The price of the PFCs hurts. But if it lasts that much longer it might be worth it.

Also for anyone who has wilwoods or any similar caliper, I just got a new caliper spreader that is awesome.

I used to have the Lisle one and that broke on me, so I bought this one:
Amazon Amazon

Super beefy, and fits the dynapros great. For $16 it's a no brainier.
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Old 03-24-2017, 08:52 PM
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Originally Posted by aidandj
Ive got a brand new set of rotors waiting to go after I finish off these dtc60s. The price of the PFCs hurts. But if it lasts that much longer it might be worth it.

Also for anyone who has wilwoods or any similar caliper, I just got a new caliper spreader that is awesome.

I used to have the Lisle one and that broke on me, so I bought this one: https://www.amazon.com/Excelvan-Spreader-Separator-Piston-Professional/dp/B015ZBOHXO/ref=redir_mobile_desktop?_encoding=UTF8&psc=1&ref_ =oh_aui_i_d_old_o1_img

Super beefy, and fits the dynapros great. For $16 it's a no brainier.
The price of the PFC hurts compared to the Hawks but they are darn good, much easier on rotors and the dust is not nearly as nasty as the Hawk DTC-60 when it comes time to clean the rotors. You can also drive on the street with the PFC without rolling through stop signs unlike the DTC. Just remember the faster get the quicker you'll go through consumables, it won't matter what pad you run.
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Old 03-24-2017, 08:55 PM
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Does PFC make a 7812 pad? I don't want to use a cotter pin on my dynapros.
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