Big Brake fun
#61
1. The ST42 in the miata BBK is made for a 0.81” (20.6mm) thick rotor. The stock rotors are 22mm thick. Small difference, but the tolerances are tight enough that stoptech doesn’t recommend using the 20.6 caliper on a 22mm rotor. They do make an STR-42 caliper specifically for a 22mm thick rotor, however.
2. Wheel clearance is really bad when you move the ST42 caliper far enough inward radially to work with a 10” rotor. You run into clearance issues with the mounting pad of the wheel, not with the spokes or the outer barrel. I’m sure there are some wheels that would clear, but 6ULs will not work without a spacer.
The good news is that the ND miata uses an 11” x 22mm rotor that’s a perfect fit for the NA/NB. I’m currently running the 22mm STR-42 caliper on my car with the 11” ND rotor and a custom bracket setup. I’ve been trying to decide whether I want to sell a few sets of brackets or just give the info back to mt.net for free. I don’t want to **** up Emilio’s thread any more so PM me for any further discussion.
2. Wheel clearance is really bad when you move the ST42 caliper far enough inward radially to work with a 10” rotor. You run into clearance issues with the mounting pad of the wheel, not with the spokes or the outer barrel. I’m sure there are some wheels that would clear, but 6ULs will not work without a spacer.
The good news is that the ND miata uses an 11” x 22mm rotor that’s a perfect fit for the NA/NB. I’m currently running the 22mm STR-42 caliper on my car with the 11” ND rotor and a custom bracket setup. I’ve been trying to decide whether I want to sell a few sets of brackets or just give the info back to mt.net for free. I don’t want to **** up Emilio’s thread any more so PM me for any further discussion.
I must note that stock NB rotors are not 22 mm thick, they are 20 mm. So this aspect is covered.
As for clearence, using the template Stoptech is providing through their website, I checked and it clears my wheels, 14X6 inch hollow spokes from a '97.
It is not roomy in there but there seems to be a clearance of 3-4 mm which is more than the 2 mm Stoptech advises in their tech support webpage.
That all for the thread. I think they are relevant with big brake fun and useful.
The rest I will pm you, thanks
#63
So what's the consensus on the different caliper options? It's seeming like ST42>Superlite>Dynapro>Dynalite? And for the rear, Stoptech > dynalite > non sport rear calipers w/ sport rotor adaptors > sport rear caliper?
I keep jumping back and forth between Trackspeed's website and V8Roadsters looking at the brake options, I'll probably just get Dynapros in the front and sport calipers in the rear unless the Stoptechs are good enough to warrant spending the extra money.
And does anyone make that sport rear rotor adapter? I think TSE used to sell it but I'm not seeing it anywhere.
I keep jumping back and forth between Trackspeed's website and V8Roadsters looking at the brake options, I'll probably just get Dynapros in the front and sport calipers in the rear unless the Stoptechs are good enough to warrant spending the extra money.
And does anyone make that sport rear rotor adapter? I think TSE used to sell it but I'm not seeing it anywhere.
#64
You can't state a hierarchy of the calipers like that. The Superlite and ST42 serve totally different purposes. IMO there is no better setup on the market for a fast road race or endurance car than our Superlite setup, but it would be a pretty poor choice for an autocross car, for instance. Same thing in the rear, the "best" caliper depends on the usage.
#65
The Superlite is a bigger caliper than the ST42. Almost twice the pad area. The Superlite compares more to the much bigger ST40.
OGK, our time attack build and Vegas, our S1 Supermiata will both get radial mount Superlites with 16mm pads. Trackspeed uses the lug mount version to allow the thicker 20mm pad.
Pad volume of the ST42 is the same as a Dynalite which is 2.1
Superlite 16mm radial is 3.8
Superlite lug mount 20mm is 4.9
The ST42 is a very rigid caliper but the pad volume is what kills it in my view. Not enough gains from the added stiffness over the Dynalite to justify the cost difference.
Our current 11.75 radial mount kit uses the Dynapro 7812 pad, 2.1 volume
OGK, our time attack build and Vegas, our S1 Supermiata will both get radial mount Superlites with 16mm pads. Trackspeed uses the lug mount version to allow the thicker 20mm pad.
Pad volume of the ST42 is the same as a Dynalite which is 2.1
Superlite 16mm radial is 3.8
Superlite lug mount 20mm is 4.9
The ST42 is a very rigid caliper but the pad volume is what kills it in my view. Not enough gains from the added stiffness over the Dynalite to justify the cost difference.
Our current 11.75 radial mount kit uses the Dynapro 7812 pad, 2.1 volume
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#66
You can't state a hierarchy of the calipers like that. The Superlite and ST42 serve totally different purposes. IMO there is no better setup on the market for a fast road race or endurance car than our Superlite setup, but it would be a pretty poor choice for an autocross car, for instance. Same thing in the rear, the "best" caliper depends on the usage.
The Superlite is a bigger caliper than the ST42. Almost twice the pad area. The Superlite compares more to the much bigger ST40.
The ST42 is a very rigid caliper but the pad volume is what kills it in my view. Not enough gains from the added stiffness over the Dynalite to justify the cost difference.
Our current 11.75 radial mount kit uses the Dynapro 7812 pad, 2.1 volume
The ST42 is a very rigid caliper but the pad volume is what kills it in my view. Not enough gains from the added stiffness over the Dynalite to justify the cost difference.
Our current 11.75 radial mount kit uses the Dynapro 7812 pad, 2.1 volume
The Integra Type R that set the record at buttonwillow duriung GTA was on optimized brakes; his rotors/caliper weights were lighter than anyone else in his class and could heat soak after 10 laps or so. But the car never does more than 4-5 laps, because Time Attack. It even sacrifices ducting and radiator airflow for aero/more downforce so the brake thermal capacity was never pushed to it's limit.
Sames goes for those wanting to choose between the biggest thing that will fit and the best thing for the application; they are often not the same thing. If the Dynalites and the ST42 kits never fade on road course racing, the pad volume is essentially irrelevant, unless we are strictly considering how often the pads would need to be replaced.
As far as stiffness is concerned - the calipers themselves have much more to do with system stiffness than say, Stainless Steel brake lines. A flexible caliper can, "lose" up to 100 lbs of braking force with line pressures equal to a caliper with 10% greater stiffness. The driver can compensate at the pedal of course, but there is more potential to stiffen up the system inside the caliper than in brake lines and master cylinder bracing combined. It's no small detail.
#69
Not that I'm aware of, but Brad can clarify if so. The 7812 is the same shape as the 7816 so the ST42 can use the 7812, but the 7816 fits too. There are 8-10 Stoptech BBKs in Lexington/Louisville and we're all running the 7816 pads. In the last WRL race we did at Mid-ohio, we saw less than 2mm of wear after an 8 hour race in a PTE car with 225 RS4s. Raybestos ST42 pads.
#70
Some prices quoted to me:
Brackets - $119.00
Rotors Slotted and Zinc Plated - $168.00
Rear SS Brake Lines - $75.00
Not sure I found anyone else that sells the bracket. The ones on Goodwin Racing are "out of stock" but the price is the same.
I'm also looking at the Track Speed Engineering kit with Dynapros, prop valve and brake ducts for the front once the holiday bonus kicks - Trackspeed 11.75 Gen2 Big Brake Kit
TDR has a cyber monday sale so I'll probably do that for now. When asked they did say the rotors are SP Performance (slotted) but I saw Stoptech and DBA slotted rotors for 30-40 less on Goodwin's site, but TDR said they will try to price match. So should I stick with the slotted, zinc plated rotors from TDR or save a few and go with StopTech/DBA? Car is a 400hp LS1 and will see some track days in the spring
Thanks
#71
You can't state a hierarchy of the calipers like that. The Superlite and ST42 serve totally different purposes. IMO there is no better setup on the market for a fast road race or endurance car than our Superlite setup, but it would be a pretty poor choice for an autocross car, for instance. Same thing in the rear, the "best" caliper depends on the usage.
For a forced induction car that will see 30 minute track sessions, autox, and a little street use, where the owner prioritizes brake feel, consistency, and low operating costs over rotational mass (light is always good but I'm not enough of an autox junkie to prioritize it), what brake setup would you recommend?
I asked that last question with caliper stiffness on my mind, I've heard some complaints about flex in Wilwood calipers and it's been my understanding that many prefer Dynapros over Dynalites for this reason. But it's hard to look at $700 options without also looking into the more expensive options, namely the Superlites and ST42, and wondering what additional benefits those would offer. It sounds like the pad size of the Superlite give it a nod for operating costs over the ST42?
At what point would you ditch the stock rear calipers?
#73
My question was overly simplistic, so let me rephrase it.
For a forced induction car that will see 30 minute track sessions, autox, and a little street use, where the owner prioritizes brake feel, consistency, and low operating costs over rotational mass (light is always good but I'm not enough of an autox junkie to prioritize it), what brake setup would you recommend?
I asked that last question with caliper stiffness on my mind, I've heard some complaints about flex in Wilwood calipers and it's been my understanding that many prefer Dynapros over Dynalites for this reason. But it's hard to look at $700 options without also looking into the more expensive options, namely the Superlites and ST42, and wondering what additional benefits those would offer. It sounds like the pad size of the Superlite give it a nod for operating costs over the ST42?
At what point would you ditch the stock rear calipers?
For a forced induction car that will see 30 minute track sessions, autox, and a little street use, where the owner prioritizes brake feel, consistency, and low operating costs over rotational mass (light is always good but I'm not enough of an autox junkie to prioritize it), what brake setup would you recommend?
I asked that last question with caliper stiffness on my mind, I've heard some complaints about flex in Wilwood calipers and it's been my understanding that many prefer Dynapros over Dynalites for this reason. But it's hard to look at $700 options without also looking into the more expensive options, namely the Superlites and ST42, and wondering what additional benefits those would offer. It sounds like the pad size of the Superlite give it a nod for operating costs over the ST42?
At what point would you ditch the stock rear calipers?
11.75" Rotors: cheap ones, 949 or Wilwood Spec 37. Whatever your flavor it will translate across all kits.
Pads: Dynapro and ST42 support the same 16mm thickness pads. In Cobalt pads I found the cost the same for either of those two at $169. Same for 12mm dynalites to so 4mm free pad with either. With the 20mm Superlites it jumped up to $269. With Hawk DTC the Dynapro 12mm (only size shown) at $92 vs Superlite 20mm at $172. If you a strong preference for a particular pad then this will weigh heavy in your decision. Do your own research here and use that info to decide.
Calipers stiffness: The STR42>ST42>Superlites>Dynapro. No huge deltas here though. Dynapro is pretty good but try and skip it if you can and go with Superlite. You current wheel size will dictate that.
When inner to outer pad taper becomes an issue. Jumping to 10.90 rotors will help up to a point. Then sport calipers are the next logical step.
Last edited by k24madness; 11-06-2018 at 09:01 PM.
#74
Nitpicking here, but... ST-42 and STR-42 start out as the same forging. ST-42 only gets the minimum required machining on bores and mounting surfaces, STR-42 gets ALL surfaces machined. They're functionally identical but the STR-42 is 0.5lb lighter and $100 more per caliper.
Last edited by jpreston; 11-22-2017 at 02:10 PM.
#75
Nitpicking here, but... ST-42 and STR-42 start out as the same forging. ST-42 only gets the minimum required machining on bores and mounting surfaces, STR-42 gets ALL surfaces machined. They're functionally identical but the STR-42 is 0.5lb lighter and $100 more per caliper.
#77
#78
The Superlite is a bigger caliper than the ST42. Almost twice the pad area. The Superlite compares more to the much bigger ST40.
OGK, our time attack build and Vegas, our S1 Supermiata will both get radial mount Superlites with 16mm pads. Trackspeed uses the lug mount version to allow the thicker 20mm pad.
Pad volume of the ST42 is the same as a Dynalite which is 2.1
Superlite 16mm radial is 3.8
Superlite lug mount 20mm is 4.9
The ST42 is a very rigid caliper but the pad volume is what kills it in my view. Not enough gains from the added stiffness over the Dynalite to justify the cost difference.
Our current 11.75 radial mount kit uses the Dynapro 7812 pad, 2.1 volume
OGK, our time attack build and Vegas, our S1 Supermiata will both get radial mount Superlites with 16mm pads. Trackspeed uses the lug mount version to allow the thicker 20mm pad.
Pad volume of the ST42 is the same as a Dynalite which is 2.1
Superlite 16mm radial is 3.8
Superlite lug mount 20mm is 4.9
The ST42 is a very rigid caliper but the pad volume is what kills it in my view. Not enough gains from the added stiffness over the Dynalite to justify the cost difference.
Our current 11.75 radial mount kit uses the Dynapro 7812 pad, 2.1 volume