Yes, I have experience with Wilwood calipers and have built many brake packages using them...Viper...Vette...will be doing Mini Coopers soon.

Back in 96 I had my first Viper and started club racing at Texas World Speedway. I got hooked and once I started actually driving well…I was burning through stock brakes in a weekend. And one time (no, not at band camp)…I actually boiled the brake fluid leaving me with NO BRAKES doing 155mph into turn one…not funny…needed new shorts! I wanted big brakes but only had the choice of Brembo or Alcons that were to the tune of $15K for a Viper! So I made my own with the goal of bolt on brakes that fit under the wheels that work with the stock master cylinder, that were balanced and safe, reasonably priced…that I could work on myself...but never at the track! I like to drive at events rather than get dirty under a car.

I evaluated all of the calipers and chose Wilwoods due to many factors starting with quality. Price was a factor too…as they are less expensive… not because they’re inferior…but because Wilwood sells more racing calipers (largely due to NASCAR) than other companies and therefore does business using lower prices. They’ve earned a reputation as throw away’s…but that’s because it’s almost easier to buy a new caliper than to rebuild one. You’de never throw away a Brembo that was part of a $15K package…($10K of which goes to support their F1 and Indy racing efforts)…simply based on the cost alone!

One part that gets overlooked about the Wilwoods vs. others is the brake pads. Most of the Wilwood calipers that are used for front brakes use a pad that is almost an inch thick! That makes for extremely long life on the track. Because of this, I found that I used one set of rotors and pads each season…which equated to about 21 events. My rotors cost about $500 to replace (for all 4) and pads $100 per axle. That’s $700 bucks for 21 events or $30 bucks in brake cost/usage per event! You simply CANNOT beat that ongoing cost with ANY OTHER KIT available! Period! Sometimes I'd swap pads due to heat cycling...but I really didn't have to. Almost all other calipers, including Brembo and StopTech use thin pads that must be changed more often and the rotors are significantly higher priced for replacement.

After using these brakes…I’ve never had brake fade or been in trouble situations due to brake failure. Quite the contrary…I usually ran at the front of the pack with significantly faster cars…due to my braking capabilities and consistency. I placed 3rd in the 2000 Viper Days (at Motorsports Ranch in Ft. Worth) in a stock engined C5 Corvette against Vipers…simply because I could out brake them. At that event…I had a full Race GTSR Viper ($275K carbon fiber car with15” Brembos) follow me into turn 1 and go straight off the track because he was way close to me and was waiting for me to brake. I use the brakes at the 1.5 cone marker where he should have been on them at the 3.5…I thought I was quite cool! He didn’t!

All of these brakes are cool. The two piece rotors really make a difference in handling too…due to weight…both unsprung and rotational. For me…I chose the Wilwoods (like I said) due to the ongoing cost of having them. About $2K per axle for the upfront cost…and $30 an event…and I didn’t have to buy new wheels unless I wanted to…I was convinced.

Later,
David Tittle

 

You raise some good points. The discussion has begun to resemble a bunch of engineers talking amongst themselves and we may be leaving most of the readers in the dark. While it's fun for us (well, perhaps not Russell, since he's feeling a bit beat up) it may not be interesting any longer for the majority. Let me try to help.

For fitment, the StopTech 332mm brakes do fit under the 17" factory wheels and the 355mm brakes under the 18" wheels, without spacers.

The issue of caliper stiffness translates directly into pedal feel. A caliper which is four times stiffer than another will, all else being equal, yield a firmer pedal and will be easier to modulate with more linear response to driver input.

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In the real world…we want brakes that are safe, that work consistently every time we want to use them

Designing for safety should be paramount in the engineer's mind. Substituting cheaper 6061 aluminum for the hats, rather than using more expensive 7075 T6 aluminum is something I would avoid, especially if a brake kit is targeted for people who might actually race the car. The latter material is much stronger and can withstand many more heat cycles. Hats are consumable items, just like pads and rotors. Depending on how hard the car has been raced, it may be necessary to replace the hats after just two friction ring (rotor) replacements or the hat might last for five or more changes.

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…look cool…stay clean

As for looking cleaner longer, the Wilwood calipers are an anodized finish. The Brembo and StopTech calipers are finished with a high temperature paint (red, black, silver or custom) which is much more durable and maintains its gloss over time.

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…don’t require a ton of maintenance (we have wives for that)…don’t make me modify my car so I can return it to factory if I sell it…don’t cost too much up front and don’t cost too much to maintain.

For ease of maintenance, the dust boots reduce the amount of work required when changing pads. Every single OEM brake in the world uses dust boots, as does StopTech and Brembo. Sure they can get vaporized at the track if you're in the Advanced or Instructor run groups with R-compound tires. For those folks, I recommend the titanium backing plate inserts. These reduce the amount of heat that hits the dust boots and can, in most cases, prevent their destruction. For street and autocross as well as most club racing, the dust boots will remain intact, protecting the piston bores from grit and grime.

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Oh yeah…we want to be able to work on them without having to employ a former F1 technician!

All of the kits described here are easy to work on. Pad changes are easier with Wilwood, Brembo, and StopTech calipers than they are with stock. Sure the Wilwood requires the extra step of cleaning the pistons during pad changes, but it's still easier than pad changes on stock calipers.

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Most all of the kits here are good and will perform very similarly. It’s simply boils down to cost now and cost over time.

That's where we disagree. I don't consider kits that lengthen stopping distance and make the brakes harder to modulate as equals to more thouroughly engineered and tested kits.

Here are some quotes from a couple race drivers who switched from Wilwood calipers to StopTech:

Charles Espenlaub, Mazda Protégé ES, Touring Car

"I teach race car driving at Road Atlanta and so I know the course well. The first time I took the car there with the StopTech system I was able to brake probably 150ft. deeper than my previous brake upgrade. The StopTech's give me excellent braking control. I love 'em!"


Roger Foo, Mazda Protege, Touring Car

“Braking played a critical role in passing. I was able to make passes under braking that I couldn’t do before with other systems."

 

LOL, I'm an engineer, and its so dark, I can't see my hands!!!

Nice discussion guys, keep it up!!!

 

I did a little research. Here's what I found:

At the upcoming Winston Cup race at Watkins Glen next weekend, the following brake companies will be represented:

Brembo: 20 - 25 cars
AP Racing: 16 - 18 cars
Alcon: 3 cars
Wilwood: 1 car

In the IRL, there are no cars running Wilwood calipers.

In CART there was only one team running Wilwood calipers and, from what I've been told, they were taken off 6 years ago and haven't been represented since.

It appears that Wilwood has been driven out of the high end of racing and is focusing on the low end market.

 

To back up Russell on this point, I've been maintaining a Wilwood-based front brake kit for a friend of mine with a 1995 Impala SS here in NJ. He's gone through 3 sets of tan pads and I'm about to change his rotors for the first time. Even with the road salt here, I haven't had to rebuild his calipers and they've been on the car since late 1999. I would not consider this aspect of the brakes to be the deciding point.

Similarly, my track Mustang has the 2-piston '93 Cobra-R front brakes and I burn the dust boots off that set-up in just one weekend. It's track-only, so I don't bother replacing them. With the 4-piston fixed calipers, I have the luxury of being able to slip 1/2mm titanium backing plates in between the pad and the caliper pistons and that is usually enough to save the dust boots from destruction. The Cobra brakes have piston clips which preclude the use of the titanium trick.

 

Hey Dave,

Thanks for the wheel fitment info and the research on where Wilwoods are being used. Why no StopTechs in that list?

While I appreciate your brand loyalty...I wonder if you’ve been to the track very much or seen some of your rotors and calipers used hard? I’ve been at the track plenty…and have worked with your products! I’ve been right next to StopTechs booth and techs actually at many Viper Days events and have even replaced a set or two of StopTechs with my packages. I’ve seen crazy things too…like novice drivers waste a brand new set of your rotors and pads in one session! Wonder why?

I know it might not sound like I like your products…I do…they’re good brakes…your lines are great…your bridge support is pretty cute…the kits are balanced well etc. But…your calipers are literally Porsche/Brembo knockoffs and there’s nothing really new about them. They are good choices for a lot of people and so are Wilwoods! What I don’t enjoy from you guys, however, is the “not invented here” attitude and the whole “condescending-got-to-pick-on-everybody-elses-stuff” marketing tactics. At track events, I’ve had Steve come over and insult me and Bob has phoned me at my house several times with respect to this very issue. It’s exactly what Russ said!

Facts: The dust boots on StopTech calipers will melt the first time you heat em' up! Titanium backing plates only make some place to store that goo when it happens. I've worked on StopTech brakes...that had either melted or dried up and crumbly dust boots leaving a worse scenario than no dust seals at all! For the street driver…or someone who drives for 30-60,000 miles in rain and snow, fording rivers and driving on dusty roads…dust seals are mandatory! But on the track…your points are pointless! Please don’t mislead.

Like you said, that red and black paint does look pretty when they’re in the box…but when they get hot…that pretty white writing turns yellow and looks the color of bad dentures with nicotine stains and the paint dulls easily and often gets impregnated with brake pad chards and worn rotor material! It’s true that the black anodize on a Wilwood fades over time too…but it doesn’t chip and stain. Face it…hot racing brakes create one of the most hostile environments (except my X-wife) that I can consider and there’s no winner on long-term looks here. Please don’t try to defame others to make your product look better?

Your 6061 vs. 7075 argument is mute and implying that there is a strength integrity issue with 6061 is silly. In fact, many argue that the brittle nature of 7075, when repeatedly heated and cooled as with racing brakes, makes the part less reliable than 6061! Go figure that! In eight years of hard-core driving I’ve yet to replace a rotor hat due to stress! I put over 22,000 track miles on my 96 GTS and it still has the original brakes on it! 6061 certainly wasn’t used to be cheap either! Furthermore, depending on the application, Russells hats are often .375” thick as opposed to .250” just for extra oompth. Lots of thought and research went into those decisions. It would take a freakin’ bulldozer to break one of those hats!

Finally, I don’t know where you got the notion that Russells package will lengthen stopping distances! The package Russ put together will dramatically shorten stopping distances and do it with consistency. The pedal is rock hard and EASY to modulate!

While not saying a bad word about StopTech brakes…we’ll get some numbers for you….but when we do…you know you won’t like em’!

Peace Out,
Tittle


P.S. Don’t ever let me creep up behind you on a track day…I’ll pass you under braking…twice!

 

MY NEW SYSTEM IS BETTER THAN BREMBO STOPTECH AP ALCON. I CUT A HOLE UNDER THE DRIVERSIDE FLOOR TO USE MY FEET TO BREAK ALA FREDDIE FLINSTONE YABA DABA DO

 

Actually...the baddest brake package I've ever created will stop a 3600lb. car or an F-18 Hornet in less than 50'......quite amazing...I know!



Tittle

 

OH HELL NO

 

If you got to Wilwood webpage, they list plenty of wins this year.

Even this "low end market" you speak of is still much more demanding then what we would be common people face at the track. Maybe I should trade in my pentium 4 computer for a IBM deepblue since that's what the big boys are using.

 

Let's put this discussion into context, lest it devolve into a pissing contest between engineers. We're discussing which brake kits are appropriate for the 350Z. It's my assumption that the audience to this thread is interested in learning about options for their daily driver 350Z which is occasionally taken to the track on weekends. Dual use cars which the owner can live with on a daily basis and then take to the track without having to deal with pad and fluid fade.

We are not talking about 400 horsepower cars with V10 engines and 465 foot pounds of torque that are swapping paint at the track.Because StopTech has not gone after that market. A better question, since you HAVE gone after the Viper market, is why are the top 10 cars in the Viper Days series not running Wilwood brakes? In fact, 75% are running StopTech and the rest are running Brembo and Alcon. This is a market you both play in, so the comparison makes more sense.

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I’ve been at the track plenty…and have worked with your products! I’ve been right next to StopTechs booth and techs actually at many Viper Days events and have even replaced a set or two of StopTechs with my packages.

Let's be specific here. You're not talking about replacing a StopTech brake kit with a Wilwood brake kit, are you? You're talking about replacing a rotor that had some pad deposition issues.

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I’ve seen crazy things too…like novice drivers waste a brand new set of your rotors and pads in one session! Wonder why?

By "waste" I'm assuming you mean he had a problem with uneven pad deposits, often caused by inappropriate selection of pads. I would be running PF 01 pads on a Viper and wouldn't even consider a club race pad if I wanted to avoid deposition.

I'm an independent dealer and also sell Brembo products. I sell products I believe in and can stand behind. The "StopTech" rep title is part of a my350z.com sponsorship agreement I have with them, since they don't have the staff to answer questions on every message board. I sell, install, and support all sorts of brake kits, so I'm in a position to help them out as well as step back and compare various kits.

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I know it might not sound like I like your products…I do…they’re good brakes…your lines are great…your bridge support is pretty cute…the kits are balanced well etc. But…your calipers are literally Porsche/Brembo knockoffs and there’s nothing really new about them. They are good choices for a lot of people and so are Wilwoods!

The lines are great. I've even had a few made for other kits at the request of customers.

The calipers are not knockoffs. Unlike the Brembo, AP, Alcon open-top calipers, StopTech has a patented, bolt-in stiffening bridge that is responsible for doubling the rigidity of the caliper. In fact, Alcon just started putting a stiffening bridge in their high-end caliper, but it's cast-in and requires that the caliper be removed to change pads.

If you take a Brembo and an AP caliper and paint them red, from 20 feet away they look identical. If you compare all these calipers with StopTech from the top, the only one that looks DIFFERENT is the StopTech.

Unlike these other calipers, the StopTech has 15 unique piston size combinations in order to come up with the proper balance that you praise.

Speaking of piston size combinations, Russell mentions that he has "properly matched the piston bore sizes of these calipers to work with the stock brake master cylinder and ABS system to maintain the appropriate brake bias." How has he done that? The 6-piston Wilwood caliper only comes with ONE combination of piston sizes. It uses four 1.12" pistons and two 1.62" pistons. Perhaps I've missed something in the various Wilwood product sheets, but I couldn't find any other piston sizes available.

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What I don’t enjoy from you guys, however, is the “not invented here” attitude and the whole “condescending-got-to-pick-on-everybody-elses-stuff” marketing tactics. At track events, I’ve had Steve come over and insult me and Bob has phoned me at my house several times with respect to this very issue. It’s exactly what Russ said!

Stoptech's marketing tactic is not to pick on other companies. You don't see them attacking Brembo. What you do see is them objecting to the claim that an inferior caliper (i.e., Wilwood) is as good as the StopTech or Brembo caliper but is cheaper because they don't make as much margin on the parts. That's simply untrue and can easily be proven in the lab and on the track.

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Facts: The dust boots on StopTech calipers will melt the first time you heat em' up! Titanium backing plates only make some place to store that goo when it happens. I've worked on StopTech brakes...that had either melted or dried up and crumbly dust boots leaving a worse scenario than no dust seals at all!

Agreed! On a 450 hp Viper going 155 mph at Road America. But it won't happen on a 350Z at the same track. I've got Instructor level customers with the smaller 332mm front StopTech kit running R-compound tires and they are NOT burning up the dust seals. The 355mm StopTech kit will run at even lower temperatures. Seal vaporizing is not an issue for these cars. It is for the Vipers.

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For the street driver…or someone who drives for 30-60,000 miles in rain and snow, fording rivers and driving on dusty roads…dust seals are mandatory! But on the track…your points are pointless! Please don’t mislead.

I'm glad we agree that seals are mandatory for street drivers. That will come as useful information for those trying to decide which brake kit to buy for their cars which are primarily driven on the street and only tracked a few times per year.

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Like you said, that red and black paint does look pretty when they’re in the box…but when they get hot…that pretty white writing turns yellow and looks the color of bad dentures with nicotine stains and the paint dulls easily and often gets impregnated with brake pad chards and worn rotor material! It’s true that the black anodize on a Wilwood fades over time too…but it doesn’t chip and stain. Face it…hot racing brakes create one of the most hostile environments (except my X-wife) that I can consider and there’s no winner on long-term looks here. Please don’t try to defame others to make your product look better?

Again, it's the difference in operating environment that becomes important. My 350Z customers are not having problems with paint discoloration. My Viper customers are. This is a 350Z board and the audience is interested to hear what will happen to THEIR brakes.

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Your 6061 vs. 7075 argument is mute and implying that there is a strength integrity issue with 6061 is silly. In fact, many argue that the brittle nature of 7075, when repeatedly heated and cooled as with racing brakes, makes the part less reliable than 6061! Go figure that!

You're simply wrong here. An Indy or CART team might consider either 2024 T3 or 7075 T6, but there's no way they would even discuss 6061. Your talking about a tensile stregth of about 45,000 psi for 6061 vs. 83,000 for 7075 T6. Show me anyone with an engineering degree who would argue that 7075 T6 is an inferior material to 6061 for a rotor hat.

Quote:

Finally, I don’t know where you got the notion that Russells package will lengthen stopping distances! The package Russ put together will dramatically shorten stopping distances and do it with consistency. The pedal is rock hard and EASY to modulate!

I got that idea from the testing we did at Camarillo Air Base on the 350Z. There was a range of additional front bias that slightly reduced stopping distance over stock. Get outside of that range and you end up increasing stopping distances. Russell's kit appears to be front biased based on the assumptions I made rooting through the Wilwood catalogs and calculating brake torque equations. I'm not stating it as fact that Russell's kit will lengthen stopping distances because I haven't tested it. But I strongly suspect the distances won't be optimal because I've been through the iterative testing to zero in on the proper balance.

I do know there's NO WAY his kit will "dramatically shorten" stopping distances. It's just not possible. You can add or subtract a few feet from stopping distance tests (60-0, 80-0, 100-0) by changing the brake bias. At the end of the day, you consider yourself a winner if you even match the factory brake distance. They usually do a very good job of figuring out the optimal balance. If you change the bias too far to the front or to the rear, you will LENGTHEN stopping distances.

Under race conditions, with repeated stops, these kits will ALL offer greater ability to absorb and shed heat and thus the stopping distances will be consistant from lap one to lap 30. But to claim that any brake kit will "dramatically" reduce stopping distance under street driving conditions is false advertising. That's not what these are for. For street drivers, they offer firmer pedal feel (depending on piston sizing), quicker reaction time, and more linear braking response. It becomes easier to threshold brake and the brakes instill a sense of confidence in the driver. But no brake kit is going to shave 30 feet from an 80-0 braking distance.

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P.S. Don’t ever let me creep up behind you on a track day…I’ll pass you under braking…twice!

Now you're scaring me. In the September Car & Driver Supercar Shootout, the StopTech equipped Viper beat the Wilwood equipped Viper by 97 feet. Just make sure you're off the driving line so you don't plant your hood into my rear bumper.

 

Sorry, I had to just say....I'm LOL!


Seriously though, a lot of good points by Dave in that post.

Don't tone down the tech too much guys...without that the discussion means nothing when it comes down to making a purchase decision.

 

Dave, Dave, Dave, Dave…Dave,

This is not a pissing match…we don’t have those here! And…I would NEVER plant a hood in your bumper…maybe a gentle nudge and a wink…but never a PLANT! J

Seriously…I’ve never swapped paint with another car and have never done the wheel to wheel racing in Viper Days like you’re probably thinking. Only club and DE’s!

The first reason that StopTech is running Viper days is because I wouldn’t pay for sponsorship. I actually sold the brake business I had in order to take care of some health related stuff and got out of making brake packages for over two years. StopTech sponsored the series and agreed to have Techs at the events…good for them. Check out the points matrix for the Viper Days series…you actually get docked points if you don’t run StopTechs! Think about it! They make a little $$$ and the Viper Days people are happy.

You say that Vipers are Z’s and shouldn’t be compared referring often to the horsepower and torque of a Viper (which you got wrong…BTW). I really don’t care if a Viper has a jet engine attached…it’s a 3,500 lb. car (soaking wet that is) and Car and Driver reports the Z at 3320 lbs. Since we’re talking about stopping as opposed to accelerating…horsepower is mute. True a Viper might be able to pull a few more MPH on the straight…and has bigger tires…but weight is weight and the cars shouldn’t be separated that much for the sake of this argument! You’re still attempting to stop a 3,200+ lb. vehicle from speed and that generates heat and wear! I’ll wager some cold beer, that any competent driver could turn your red calipers maroon with the addition of some sticky tires! I’ve passed a lot of instructors.

6061 vs. 7075…like always…you speak using terms like inferior. Please understand that NO ONE is contesting that 7075 IS BETTER than 6061! I repeat…IT’S BETTER material than 6061! You’re losing sight of CLEAR FACT that 6061 is WAY BEYOND ADEQUATE for this application! To use your INFERIOR approach…StopTechs are INFERIOR to carbon/carbon rotor pad combinations and you should desist making them immediately because of this! When you finally use only the perfect materials…will you be permitted back into the brake industry at which time I’m sure you will take over and wholly consume all forms of racing! (Yes…I’m being sarcastic!)

Russell’s brakes are balanced because the kit is calibrated for 4 wheel use. You can scrub the numbers seven ways to Sunday and you CANNOT disprove the balance of the system. I’ve had this argument before and the most **** retentive engineers out there did the math independently. Proof is in the pedal anyway!

Yes…although it’s been a while…I have replaced two front StopTech packages with mine!

And finally, the all-important question. Why did a StopTech equipped Viper stop quicker than a Wilwood equipped Viper? Well Dave…there are so many reasons…it’s not even funny…a few are as follows:

The Apex Lethal Car is an ACR which uses Koni shocks and springs with light spring rates that allow forward weight transfer which is good for braking. The Hennessey car is using Penske’s with 600 and 900lb springs that don’t allow much direct forward weight transfer. The do, however, work better on the road course which is why your car got beat by over a FULL SECOND on it’s best lap! Next, the StopTech car has 14” brakes as opposed to 13” on the Wilwood! Now finally, the StopTech car is a 2001 compared to 1997 (Wilwood) with the MAJOR GLARING DIFFERENCE BEING (drum roll please)…ABS! ABS! ABS! Tell him what he won Bob…his ABS equipped car stops quicker than a non-abs car that is notorious for the longest stopping distances possible!

I can’t believe you tried to pull that Dave on a fellow brake nerd! What you should’ve really been asking, “is why the Mosler Proton equipped with a Wilwood brake package spanked your StopTech Viper by an additional 14 feet?” It was second only to the macked out Auto Authority Porsche. Please don’t say it’s due to the weight either…yes the Proton is lighter…but that car had the wrong tires with –2.5 degrees camber and STREET PADS!!!

BTW…I designed that kit on the Mosler…and it’s remarkably similar to Russell’s package! I’m just sayin’!

Peace Out,
Tittle

P.S. WAR BRAKES! WAR ABS! WAR STOPPING POWER!

 

I think it was Russell who first used the pissing squirrel icon! First time I had seen it. Almost lost my Pepsi!

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The first reason that StopTech is running Viper days is because I wouldn’t pay for sponsorship. I actually sold the brake business I had in order to take care of some health related stuff and got out of making brake packages for over two years. StopTech sponsored the series and agreed to have Techs at the events…good for them. Check out the points matrix for the Viper Days series…you actually get docked points if you don’t run StopTechs! Think about it! They make a little $$$ and the Viper Days people are happy.

I hope you got the health stuff sorted out. That's the kind of thing that puts cars and brakes and other toys into their proper perspective.

Here's the rules matrix: http://www.viperdays.com/rulesmatrix.html

If you use the StopTech OE replacement rotors, you get a point added to your classification level. Too many points and you get bumped up to the next higher class. If you use "Other OE Replacement" rotors, you get 2 points added. But that's because those other OE rotor replacements are 2-piece whereas the StopTech is 1-piece.

None of this has anything to do with running a 4-wheel StopTech big brake kit. The points penalty is the same for all aftermarket kits. People run the StopTech brakes in Viper Days because they work well. Not because StopTech paid $2500 in sponsorship money to the club.

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You say that Vipers are Z’s and shouldn’t be compared referring often to the horsepower and torque of a Viper (which you got wrong…BTW). I really don’t care if a Viper has a jet engine attached…it’s a 3,500 lb. car (soaking wet that is) and Car and Driver reports the Z at 3320 lbs. Since we’re talking about stopping as opposed to accelerating…horsepower is mute. True a Viper might be able to pull a few more MPH on the straight…and has bigger tires…but weight is weight and the cars shouldn’t be separated that much for the sake of this argument! You’re still attempting to stop a 3,200+ lb. vehicle from speed and that generates heat and wear! I’ll wager some cold beer, that any competent driver could turn your red calipers maroon with the addition of some sticky tires! I’ve passed a lot of instructors.

I like your preferred currency for wagering! For the record, I really enjoy Celebrator Doppelbock. brewed by Ayinger.

The weight isn't so much the issue for me as is the speed at the beginning of the braking zone. Energy converted to heat goes up linearly with mass, but goes up with the square of the velocity. I know you already knew this. That's an aside for some in the audience who might not. To put it into perspective, as much kinetic energy is turned into heat slowing from 120mph to 104 as is converted by stopping from 60mph. The heat generated by slowing a car from speeds of 10 or 20 mph higher is quite significant. You just don't see the same wear on cars in the 350Z class (yes, even with R-compound tires) as you do in the Viper community. Those guys are tough on brakes!

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6061 vs. 7075…like always…you speak using terms like inferior. Please understand that NO ONE is contesting that 7075 IS BETTER than 6061! I repeat…IT’S BETTER material than 6061! You’re losing sight of CLEAR FACT that 6061 is WAY BEYOND ADEQUATE for this application!

Actually you did say 7075 was inferior in your last post. You claimed that "many argue that the brittle nature of 7075, when repeatedly heated and cooled as with racing brakes, makes the part less reliable than 6061." I haven't met any of those folks yet.

Yes and yes. We agree on both terms. Running the numbers on Russell's 4-wheel set-up looks like he put together a kit with decent balance. I mentioned that in one of my early posts. However, he's also selling the front half of that kit by itself for $2450. That's the package I'm concerend about lengthening stopping distance.

And the proof is in the pedal and the testing. We'll have to wait until one of the magazines does an independent test because I'm sure neither company would trust the other to run the evaluations. Even though the technique seems to preclude gaming the system (See: http://www.zeckhausen.com/Testing_Brakes.htm) I would be reluctant to have someone run the tests who had an interest in the outcome!

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Now finally, the StopTech car is a 2001 compared to 1997 (Wilwood) with the MAJOR GLARING DIFFERENCE BEING (drum roll please)…ABS! ABS! ABS! Tell him what he won Bob…his ABS equipped car stops quicker than a non-abs car that is notorious for the longest stopping distances possible!

OK, then lets compare the StopTech Viper to the GTS ACR Viper Coupe that also had ABS. The StopTech equipped Viper beat that one by 105 feet.

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I can’t believe you tried to pull that Dave on a fellow brake nerd! What you should’ve really been asking, “is why the Mosler Proton equipped with a Wilwood brake package spanked your StopTech Viper by an additional 14 feet?” It was second only to the macked out Auto Authority Porsche. Please don’t say it’s due to the weight either…yes the Proton is lighter…but that car had the wrong tires with –2.5 degrees camber and STREET PADS!!!

My fellow brake nerd - the Mosler is a 2200 pound car, but I won't mention the weight difference. (Oops!) The key to the Mosler's terrific stopping distance is the front/rear weight distribution. At 37/63 the mid-engined Mosler was able to do more work with the rear brakes. The Viper has a 45/55 static weight distribution, so it can't do as much with the rear tires under braking.

As an aside, the Mosler should have beaten the Porsche which didn't have as much rear bias.

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BTW…I designed that kit on the Mosler…and it’s remarkably similar to Russell’s package! I’m just sayin’!

I'm jealous of the time you probably got to spend driving the Mosler. That's the great thing about working in this business is that we get to play with some really cool toys.

I'm heading up to NH for the weekend and out of "radio contact" so you get a free pass on the next few posts.

Have a great weekend all!

 

First, thanks for the discussion guys, wish we could get more like it for other components.

Dilusi,
Could you address the following point DZeckhausen brought up?

"Speaking of piston size combinations, Russell mentions that he has "properly matched the piston bore sizes of these calipers to work with the stock brake master cylinder and ABS system to maintain the appropriate brake bias." How has he done that? The 6-piston Wilwood caliper only comes with ONE combination of piston sizes. It uses four 1.12" pistons and two 1.62" pistons. Perhaps I've missed something in the various Wilwood product sheets, but I couldn't find any other piston sizes available."

 

Hey Sands,

Sure I will...will someone please remind me of the piston diameters both front and rear for the Z? I had a folder here...but have misplaced it.

Thanks

 

OEM

Front single 57.2 mm (2.252") rear single 42.86mm (1.6874")

Brembo
Front four two each 44 mm (1.73") and 38 mm (1.50)

rear two 40 mm (1.575")

source is ESM 350Z manual.

 

OK guys, I feel that I have learned a lot in this trend, but I still have one problem, I pointed out earlier what precision had told me on the inexpensive kit that started this discussion:

I guess what I am looking for is an answer to this. Is this kit worth the time, or will it make things worse??? Should I stay stock, instead of even thinking about a kit with inadequate testing??

 

With brakes, I would not suggest becoming the test mule. If PB starts selling these brake kits like gangbusters and their customers are thrilled and they are winning races, then by all means, compare the available options, pick the kit which fits your budget and wheels and get it. But I wouldn't rush out to buy a new kit that hasn't been tested by the vendor, nor has it been thouroughly wrung out by their customers. That is, unless you have an unlimited budget of money and time and are doing this because you are curious and want to compare all the available options yourself.

Are you doing this in order to improve your brakes with the least amount of pain and money? Or is this a quest that you dont mind taking that carries with it some risk of failure?

 

Okay Girls,

I spun the numbers and the results are pretty interesting. I'd like to add the StopTech numbers in there for real comparisons. If someone will get the the bore diameters...I'll add them.

As you can see...
the numbers don't lie.

What you should look at are the totals...especially the overall area total...and then the final ratios. Russells kit is the LOWEST by overall area (by a tiny fraction) and uses less fluid bias to the rear...offset by a 13.6" diameter rotor...to create the correct physical bias and rear braking.

Consider that he's using 6 smaller pistons over the brake pad...which results in better distribution of force and less pad taper/wear conditions.

As you can also see...using Russ's brakes only in the front WILL NOT affect the fluid bias as implied...actually it'll help it a little.

Hope this helps.

Tittle