New Racing Brake kit

[TURBO2GO]

Looks like Racing brake has a new BBK for the NSX, including new aluminum calipers now that is very reasonably priced. This is only about $300 more than the factory caliper/oversized rotor upgrade kit. They only offer a front kit, which may be fine. Does anyone have any comments/input/experience with this? I just wrote them to find out what if any weight savings there will be.

I do track my car so I am looking for performance. I don't think I need the really crazy BBK kits because of these reasons:

1) I think the NSX is light enough and I am concentrating on getting my car well below 3000 pounds. At 2700-2800 pounds, I just think a huge BBK is way overkill and it adds weight.

2) I don't think my driving is at the pro level where I would need a really big kit and I only am able to get a few track days in a year. My stock brakes seem to be fine but I may need to change my rotors because I am getting a very small vibration and think one rotor may have a slight warp. So I may as well do an upgrade.

I have done a ton of research and talked to a lot of racers, and am unconvinced that you must have a 4 wheel kit for balance. Maybe someone like Billy Johnson would, but I am not sure I would. Plus I think you can just get a balancer and make the correct adjustments. If you disagree tell me why.

Here is the link, check it out:

http://www.racingbrake.com/NSX_FRONT_91_05_p/2128-311-4331.htm

 

[asylum]

Everybody will come with its pros/cons. So I will tell you mines : I would go with a BBK only on an heavily tracked car running slick tires with a (very) experimented driver and I would take the full kit for all 4 wheels to keep the brake balance.

Why ?

- Having driven my NSX at the track many times, with some brake upgrades (pads, cooling, fluid, brake lines) I never had problems of fading.

- I have no problem to block my slick tires so their power is sufficient with good pads. A BBK can help a little bit because they will bite more when you hammer the brake pedal. This first second is the most important of the braking if you want to shorten the brake distance. But to really get the benefit of the BBK when hammering the brakes, you must know the layout of the track by heart to know exactly when hammering the brakes. During the braking, it is the grip of your tires that is the limiting factor.

- My rotors get cracked or wrapped after some track events (5 to 10 for exemple). You will get more trackdays with BBK rotors. But they are more expensive.

Before going with a BBK, first upgrade the stock brakes and try to use all their potential.

 

[Liquid]

From what I've read, I think the first brake upgrade after more aggressive pads (and perhaps upgraded rotors) is adding brake ducts. If it were me and the decision was made from a purely performance standpoint (vs. the look of a BBK), I would start there and then evaluate whether additional improvements were needed.

I have not experienced any fading at the track and, as you know, Bob has done 75 or so track days with the stock calipers and had no problems.

 

[stuntman]

Rotors rarely warp anymore. Often uneven pad deposits are the culprit from a variety of causes: poor bed-in procedure, poor cool-down, poor quality pad that doesn't lay down a consistant layer of material on the rotor, etc...

Keep in mind stock calipers are heavy, a BBK might not increase the unsprung weight much if atall.

What pads are you currently running?
Tire size and compound front and rear?
Stock power levels?
Are you fading your stock brakes?

While i'm one to first recommend SS lines, better fluid and pads, I could agree that there are situations where a larger diameter rotor and caliper (BBK if you will) would be beneficial over the stock system. For example, Prime member Ryneen really pushes his 235/275 R-compound shod N/A car to the limit, and for his application, his off-the-shelf Brembo GT "Lotus" setup with stock rear brakes have been a helpful upgrade.

Even on mid-engine cars, the front brakes do the majority of the braking. There are many ways to balance the car from a proportioning valve to different brake pads front and rear. Despite many people being hesitant to use different pads F-R, many race teams do this on a regular basis. =You do not have to upgrade both front and rear brake systms at the same time.

I haven't tried RB's new calipers but have a lot of experience with their older ones. I would recommend Brembo's "Lotus" GT, Performance Friction's 2pc or monoblock calipers (Same construction as the Super GT brakes and Daytona Prototypes), Stoptech offers great products, and for a competitve price to RB, I liked Rotora's new products (which really impressed me for the price point). We won the 25 hours of Thunderhill and came 2nd overall on Rotora brakes:

If you have an early generation car with smaller rotors, keep in mind this car was designed with 15" front wheels and 205s. The demands of a modern 215 street tire is a lot greater than a 205 back in the early 90's, let alone a 235 width R-compound front tire. Track use with this much more front grip can overpower the limitations of the stock brakes, maybe not once, but over sustained lapping they can heat soak. The later cars have larger rotors and I would be more inclined to recommend just upgrading the pads/fluid/lines if you havn't already because they increaed the size of the rotor due to more room from the larger wheels/progression of the automotive community as a whole to better brakes and larger wheels. Ducting and pads should be fine for the later model cars, but that dosn't mean that its bad to upgrade to a BBK. If you have an early car, it might be a better idea to upgrade, but it depends on your situation: car mods, driving ability, etc...

Figure out what your needs are, if bigger brakes are in order, you can balance them out despite some saying otherwise. Next figure out what price point, brand, looks, function aspects and more that make sense to you and go from there.


Billy

 

[Frank Spano]

Does anyone know if these will fit the stock wheels? Thanks, Frank

 

[TURBO2GO]

Billy much thanks for the detailed reply. My car is a 2005. I have no fade. I do have a very slight vibration in my wheel on hard braking that I noticed only on the track. The situation was that at last year's trackmasters event my instructor, who I did not get along with all that well and this was one reason, took my car for 8 to 10 hard laps on open track. My rotors looked visibly different after that and I had a slight vibration after. That was on stock pads, as I only had about 9K miles on my car at the time. Then I threw in some Hawk HP+, bedded them according to the stoptech method on their site, and it seemed to be fine. I did not replace these, drove maybe another 2K miles on the street with them, and didn't notice anything other than squealing and dust. At this year's trackmasters, I did notice some slight vibration. Very little, but enough that I noticed. So I thought my front were warped. You are saying they don't warp anymore. So I thought I needed new front rotors, and if I am changing them anyway, why not upgrade. That is why I was looking at the RB's.

I think better brakes FEEL better, I am fully aware that the limiting factor are the tires and on repeated braking, heat. I am not unhappy with the stock brakes at all. I am running a CTSC, and on the back straight of the Glen I can and have on occasion been close to 130. Maybe more... I actually let off because I am still hesitant at that rate. My tires are Falken Azenis RT615's.

So what should I do about this slight vibration? just replace the rotors? It may well just be some residue...

On another note, a good stoptech kit can be had for $1700-1800 for the fronts, but it needs small spacers which I am not sure I like. To do the whole set with ebrake, now we are talking $5K. Just like you said, many people have told me that the fronts are carrying the load and that the stock rears may be just fine, certainly for my level. To me its just like oversteer/understeer, there are a lot of ways to tune and correct besides just one component. If I was to do a BBK other than an inexpensive rotor upgrade I would probably just talk to titaniumdave, because I like the stuff he puts together.

 

[stuntman]

Billy much thanks for the detailed reply. My car is a 2005. I have no fade. I do have a very slight vibration in my wheel on hard braking that I noticed only on the track. The situation was that at last year's trackmasters event my instructor, who I did not get along with all that well and this was one reason, took my car for 8 to 10 hard laps on open track. My rotors looked visibly different after that and I had a slight vibration after. That was on stock pads, as I only had about 9K miles on my car at the time. Then I threw in some Hawk HP+, bedded them according to the stoptech method on their site, and it seemed to be fine. I did not replace these, drove maybe another 2K miles on the street with them, and didn't notice anything other than squealing and dust. At this year's trackmasters, I did notice some slight vibration. Very little, but enough that I noticed. So I thought my front were warped. You are saying they don't warp anymore. So I thought I needed new front rotors, and if I am changing them anyway, why not upgrade. That is why I was looking at the RB's.

I think better brakes FEEL better, I am fully aware that the limiting factor are the tires and on repeated braking, heat. I am not unhappy with the stock brakes at all. I am running a CTSC, and on the back straight of the Glen I can and have on occasion been close to 130. Maybe more... I actually let off because I am still hesitant at that rate. My tires are Falken Azenis RT615's.

So what should I do about this slight vibration? just replace the rotors? It may well just be some residue...

On another note, a good stoptech kit can be had for $1700-1800 for the fronts, but it needs small spacers which I am not sure I like. To do the whole set with ebrake, now we are talking $5K. Just like you said, many people have told me that the fronts are carrying the load and that the stock rears may be just fine, certainly for my level. To me its just like oversteer/understeer, there are a lot of ways to tune and correct besides just one component. If I was to do a BBK other than an inexpensive rotor upgrade I would probably just talk to titaniumdave, because I like the stuff he puts together.

I'm often hesitant with all of these so-called "instructors" out there. It seems like everyone and their mom whose done a few track days can become an instructor.

I could easily see what you describe happening. There's a chance he glazed the pads, didn't cool the brakes down, or the high heat affecting the pad transfer to the rotor when the instructor drove your stock pads hard. More likely, the bedding in of the HP+s on top of the stock pad material in the rotor caused the uneven pad deposit problem and corresponding vibration. HP+s are a more aggressive street pad and not in the category in which people recommend when saying "upgrade the pads".

The cheapest solution would be to turn the rotors and re-bed in the HP+s (or better yet, bed in new pads on the new rotor since the HP+s could be slightly contaminated).

You could buy new stock rotors with new pads, this is probably sufficient for your track use since you do have the updated/larger rotors. This would be my recommendation.

A BBK will require wheel spacers depending on which wheels you have. The Stoptech calipers as Titanium Dave's F50 calipers are very bulky and large. I already stated the benefits of this. BBK's often "Feel" better because of the longer lever arm (caliper acting on larger diameter rotor) of the BBK, and thus the initial bite, torque, and grip is higher.

Overall, I would just say turn the rotors, replace them, and either way change the pads out to Carbotech XP8.

Ideally, if you have the time and means, having a dedicated set of front rotors and aggressive street pads that you change out when you get to the track would be the ticket to keep your race pads on your race rotor and street pads on your street rotor.

Its really your choice, but there are better street pads out there. Same with tires, yes the 615's are a hell of a deal/ bang for buck, but there are also better street tires out there: Yokohama AD07/AD08, Toyo R1R, Nitto NT05, Dunlop Starspec, Bridgestone RE-11, RE01R, etc...

 

[ediddynsx]

Dave,


I have the RB kit and it works great for street and some track use. For the money its a great kit and I am on rebuilt stock calipers. The only issue I had with them is that the caliper had to be slightly grinded down to fit. Otherwise its fine and I have never looked back from stock.


Now if you track alot and you have the skills like of a Billy Johnson then something of a Brembo GT or AP kit would be better.

I have posted pics of my setup with 17, 18 combo.

 

[WingZ]

Overall, I would just say turn the rotors, replace them, and either way change the pads out to Carbotech XP8.

Ideally, if you have the time and means, having a dedicated set of front rotors and aggressive street pads that you change out when you get to the track would be the ticket to keep your race pads on your race rotor and street pads on your street rotor.

Dave I run the Carbotech XP8 and love them. I run the NSX-R pads on the street. If you want to do new rotors do the two piece by racing brake as they save you 3 pounds per wheel in the front and 1.6 in the rear per wheel. Almost 10lbs of unsprung weight at the wheels.

Its really your choice, but there are better street pads out there. Same with tires, yes the 615's are a hell of a deal/ bang for buck, but there are also better street tires out there: Yokohama AD07/AD08, Toyo R1R, Nitto NT05, Dunlop Starspec, Bridgestone RE-11, RE01R, etc...

Yeah the RT615's got old fast but since Dave is running the stock wheels he didn't have too much choice. I run the RE01R but had to import the front as they didn't sell the 215/40/17 in the US. Only two of the tires mentioned can be done in the stock size. Those being the AD08 and the Dunlop Star Spec. I'm going to run the AD08 this year and suggest Dave do the same. The Dunlops are cheaper but don't run consistent from everything I've heard.

 

[TURBO2GO]

Overall, I would just say turn the rotors, replace them, and either way change the pads out to Carbotech XP8.

Ideally, if you have the time and means, having a dedicated set of front rotors and aggressive street pads that you change out when you get to the track would be the ticket to keep your race pads on your race rotor and street pads on your street rotor.

Its really your choice, but there are better street pads out there. Same with tires, yes the 615's are a hell of a deal/ bang for buck, but there are also better street tires out there: Yokohama AD07/AD08, Toyo R1R, Nitto NT05, Dunlop Starspec, Bridgestone RE-11, RE01R, etc...

I didn't know they still turned rotors. Do they? How much needs to be shaved to get the shit off? Also, what do you think of WingZ's suggestion of the RB 2 piece rotors in stock size, it will save 11 pounds and run a little cooler, no?

Dave,


I have the RB kit and it works great for street and some track use. For the money its a great kit and I am on rebuilt stock calipers. I have posted pics of my setup with 17, 18 combo.

Can you point me towards your pics? I actually bought a set of the RB oversized rotors a while back then sold them before I installed them At a $300 loss. I didn't want to grind the factory caliper, and I also saw some pics posted... maybe by Billy... not sure... where the two pieces came clean apart. I contacted RB on that, sent them pics, and they gave me the answer of "well we have no idea what they did so we can't say what happened". I just don't want to ever risk any problems on the track when I am at 100+ MPH.

Dave I run the Carbotech XP8 and love them. Those being the AD08 and the Dunlop Star Spec. I'm going to run the AD08 this year and suggest Dave do the same. The Dunlops are cheaper but don't run consistent from everything I've heard.

Do the carbotech XP8's make noise? My hawks finally became pretty noisy. My tires are also almost worn out. I got about 9K miles out of them. They still handled well in the wet and were great on the track. I was very happy with the 615's. I don't know... I guess not Billy's favorites. Maybe I will give the Strarspec a try now.

Thanks for all the feedback guys.

 

[TURBO2GO]

Just looked at the Star Spec on dunlop's site.... it certainly doesn't look as sticky as the 615's. Way more grooves... lol.... you guys sure these stick?

versus:

I want stick in the dry. I drove through a monsoon on the way to Watkins with 50% tread on the azenis and they were fine. I don't drive my NSX when it rains unless I get caught. Its a sunny day and part time track car.

 

[WingZ]

Do the carbotech XP8's make noise?

Oh God yes! Don't let anyone tell you otherwise:biggrin: I tried running them on the street and couldn't stand it! I know your trying to find a good comprise but trust me those aren't it. Brake pads take like 20 mins just switch them out bro!

 

[WingZ]

Just looked at the Star Spec on dunlop's site.... it certainly doesn't look as sticky as the 615's. Way more grooves... lol.... you guys sure these stick?

versus:

I want stick in the dry. I drove through a monsoon on the way to Watkins with 50% tread on the azenis and they were fine. I don't drive my NSX when it rains unless I get caught. Its a sunny day and part time track car.

http://www.tirerack.com/tires/tests...el=Direzza+Sport+Z1+Star+Spec&tirePageLocQty=

The Dunlops won this comparison but at the track the guys who are winning were running the Yoko AD07. The AD08 is superior to that one. Don't go cheap on your rubber after spending so much on both your car and your mods. The Falkens were good for about one season then everyone else upped their game.

 

[TURBO2GO]

http://www.tirerack.com/tires/tests...el=Direzza+Sport+Z1+Star+Spec&tirePageLocQty=

The Dunlops won this comparison but at the track the guys who are winning were running the Yoko AD07. The AD08 is superior to that one. Don't go cheap on your rubber after spending so much on both your car and your mods. The Falkens were good for about one season then everyone else upped their game.

I didn't go cheap. The Falkens were the best dry traction tires at the time. These Dunlops are priced much lower than the AD08. The thing is I am getting 8K miles out of a set. So it is kind of a disposable item. Do you like the AD08 better or the Star Spec? Also are you running one set of rotors with the different pads? Yeah I know switching it out is fast. Man this thread is going multiple directions now.

 

[CL65 Captain]

According to the new Grassroots Motorsports mag, the new Kuhmo XS is the new king of the street, followed by the RE-11. Falken 615s came in last. I liked that tire. However, the Kuhmo XS is going to be my next set - they're cheap too.

 

[WingZ]

I didn't go cheap. The Falkens were the best dry traction tires at the time. These Dunlops are priced much lower than the AD08. The thing is I am getting 8K miles out of a set. So it is kind of a disposable item. Do you like the AD08 better or the Star Spec? Also are you running one set of rotors with the different pads? Yeah I know switching it out is fast. Man this thread is going multiple directions now.

Maybe disposable but it's the cars contact to the road. From what I've heard the AD08 is the more consistent tire although the Dunlop posts the fastest lap. Honestly I'm torn between the two. No still running just the OEM rotors although my buddy who designs rotors says mine are what they show people as an example of bad rotors:biggrin:

According to the new Grassroots Motorsports mag, the new Kuhmo XS is the new king of the street, followed by the RE-11. Falken 615s came in last. I liked that tire. However, the Kuhmo XS is going to be my next set - they're cheap too.

Only thing is neither the XS or the RE-11 offer a 215/40/17 for the front. Was the AD08/AD07 or Dunlop in that test?

 

[TURBO2GO]

According to the new Grassroots Motorsports mag, the new Kuhmo XS is the new king of the street, followed by the RE-11. Falken 615s came in last. I liked that tire. However, the Kuhmo XS is going to be my next set - they're cheap too.

Can't find the article... got a link? WingZ is right no 215/40's. Go celtics.

 

[WingZ]

Dave dude check it out I'd asked RB about the weight savings and this is their reply

Perry

Thanks for your inquiry. We recently received a similar inquiry from another customer.



There is also weight savings in the caliper. We estimate the OE caliper to be about 8 or 9 pounds. Our RB4045 calipers weigh about 5 pounds each.



The OE bracket weighs @3 lbs while our aluminum adaptor is about 0.8 lbs.



If you purchase the kit with two piece rotor it can save you additional 3-4 lbs per rotor, which can translate into 4-5 times of static weight saving so overall you can save 35-40 lbs per axle.



In addition to weight saving some of the noted advantages of this kit over OE are: Ease of replacing pads, a wider variety of brake compound choices, great improvement on performance and looks, easy to maintain etc.



If you upgrade to the front aluminum caliper kit, an optimally balanced system will also have an upgraded rear OE caliper BBK.



Please let us know if you have any other questions.



Mike

35-40lbs weight savings per axle????? Drooooool:biggrin:

 

[ediddynsx]

I didn't know they still turned rotors. Do they? How much needs to be shaved to get the shit off? Also, what do you think of WingZ's suggestion of the RB 2 piece rotors in stock size, it will save 11 pounds and run a little cooler, no?



Can you point me towards your pics? I actually bought a set of the RB oversized rotors a while back then sold them before I installed them At a $300 loss. I didn't want to grind the factory caliper, and I also saw some pics posted... maybe by Billy... not sure... where the two pieces came clean apart. I contacted RB on that, sent them pics, and they gave me the answer of "well we have no idea what they did so we can't say what happened". I just don't want to ever risk any problems on the track when I am at 100+ MPH.



Do the carbotech XP8's make noise? My hawks finally became pretty noisy. My tires are also almost worn out. I got about 9K miles out of them. They still handled well in the wet and were great on the track. I was very happy with the 615's. I don't know... I guess not Billy's favorites. Maybe I will give the Strarspec a try now.

Thanks for all the feedback guys.

Dave,


The shaving was just done to clear my wheels, theres wasn't alot to grind down to make it fit. It was just on some of the edges on the caliper.......Me, Jon Martin, Anil, and 2 other people were one of the first to get them for the NSX when they just came out a few years ago. I had my calipers powdercoated and rebuilt to type-r specs. Heres a pic of how it looks on with my wheels.

 

[stuntman]

I didn't know they still turned rotors. Do they? How much needs to be shaved to get the shit off? Also, what do you think of WingZ's suggestion of the RB 2 piece rotors in stock size, it will save 11 pounds and run a little cooler, no?

Can you point me towards your pics? I actually bought a set of the RB oversized rotors a while back then sold them before I installed them At a $300 loss. I didn't want to grind the factory caliper, and I also saw some pics posted... maybe by Billy... not sure... where the two pieces came clean apart. I contacted RB on that, sent them pics, and they gave me the answer of "well we have no idea what they did so we can't say what happened". I just don't want to ever risk any problems on the track when I am at 100+ MPH.

Do the carbotech XP8's make noise? My hawks finally became pretty noisy. My tires are also almost worn out. I got about 9K miles out of them. They still handled well in the wet and were great on the track. I was very happy with the 615's. I don't know... I guess not Billy's favorites. Maybe I will give the Strarspec a try now.

You can get rotors turned anywhere. I had them done on my NSX at some dumpy back-alley shop that had a lathe for $5 each. They might take off a millimeter or two, nothing substantial, but enough to 'clean' the rotor. An aggressive track pad with a high metal content can have a similar result but possibly at the cost of contaminating the pad.

We've run the RB 2pc rotor and calipers on the old silver "Factor-X/Seamless" Modified-class NSX. I've also run RB 2pc rotors a few years ago on a Grand-Am Koni Challenge car. Despite losing few lbs, IMO (especially for your application) stick with the stock rotors, we didn't notice huge gains in performance in a very regulated series where 5hp makes a huge difference in competitiveness. Since tenths of the second probably doesn't separate winning from losing for you (and even if it does like it did for our Koni car), we didn't see huge gains. Despite this, we had a catastrophic failure of RB's 2pc rotor, cracked many 2pc rotors from regular use on the FX car, and had noticeable caliper flex under the demands of the FX500 Time Attack car. I was not pleased how RB handled any of these concerns or problems and I do not see any of their products in any form of professional or semi-pro motorsports to further develop and test their products. They had a great opportunity with us when we were fighting for the championship, but the failure almost caused us a DNF (let alone crash) and they were not interested in working with us or learning from what happened here to make better street products. They seemed more interested in just selling street products rather than developing products in this arena like most reputable companies do (Performance Friction, Brembo, AP, Alcon, StopTech, Rotora, Spoon, Project Mu, Cobalt Friction, Pagid, etc...)

I believe the spoon caliper with the stock rotors also nets a lighter unsprung weight over stock, and if you really want to go to a 2pc BBK for a similar price, Rotora actively works with racing teams to develop and test products and finishing the 25 Hours of Thunderhill is an accomplishment, let alone winning it.

Tires:
The 615's aren't my favorite, but they are fun, cheap, last a while, and work great at cooler temps. If the track temps are below 75*F, the 615 makes tire noise, competitive amount of grip, and are predictable. Hot ambient and track temps changes the characteristic of the 615 to make no noise, are hard to predict, get 'greasy' within a lap or two, and are not that great to learn on. If you live out here in Southern California where its always 80-100*F, the 615's are often a poor choice. In winter over here, they are awesome, competitive (set a S2000 track record on a local track in winter), and would be my choice for the price.

For the June 2009 issue of Grassroot motorsports, tires were tested in 15 inch sizes on a honda civic on 205/50-15, except for RE01R (195/50-15) and Starspec (195/55-15)

6th - Falken RT 615 Mean time: 35.302 Sec Quick time 35.125 Sec.
5th - Dunlop Direzza Sport Z1 Star Spec Mean time: 35.209 sec. Quick time 35.061
4th -Toyo Proxes R1R Mean time: 34.522 sec Quick Time 34.452 sec
3rd- Bridgestone RE-01R Mean time: 34.478 sec Quick Time 34.430 sec.
2nd- Bridgestone Potenza RE-11 Mean time: 34.266 Quick time 34.238 sec.
1st - Kumho ECSTA XS Mean time :34.170 Quick Time 34.030 sec.

All tires were shaved to 3/32nd and test performed on an Autocross set up.

*** This was done on an Autocross. Autocross tire demands are different from road course. Autocross tires start at ambient temps, have lower speeds, lower loading forces acting on the tire, and last ~1 minute or less. Road course use involves higher speeds, higher loads, longer sustained loads, longer runs (1.5-3.5 minute laps) - for multiple laps in a 10-30 minute session, etc... Personally its neat to see the 'ballparks' of autocross tests, but take it with a grain of salt. 2 tenths during this test could be far greater + or - depending on how the tire acts from said road course demands.

Nitto's NT05 is a great tire/price, but Bridgestone's new RE11 and Yokohama's AD08 are a step ahead. While many other manufacturers either have a great tire or equal to (if not barely eclipsing) the current best tires (including AD07), the AD08 is coming out and should set the bar once again for someone else to try to beat it. Tire wars are fun.

Dave dude check it out I'd asked RB about the weight savings and this is their reply

35-40lbs weight savings per axle????? Drooooool:biggrin:

We estimate the OE caliper to be about 8 or 9 pounds. Our RB4045 calipers weigh about 5 pounds each. best case 4lb gain

The OE bracket weighs @3 lbs while our aluminum adaptor is about 0.8 lbs. Best case 2lb gain

If you purchase the kit with two piece rotor it can save you additional 3-4 lbs per rotor Best case 4lb gain

= best case total 10lb gain per corner
which can translate into 4-5 times of static weight saving so overall you can save 35-40 lbs per axle. assuming a ~ 1lb unsprung = 4lbs sprung weight, i've seen figures up to =6lbs. Regardless its a figure.

10lbs per corner is pretty big, 40lbs overall shedding from the car (replacing front and rear calipers). Keep in mind what wheels/tires you have. Tires can vary in weight from manufacturer to manufacturer let alone different sizes. Same with wheels, all of these can see huge weight gains especially if you run 17, 18, let alone 19" wheels that aren't superlight.

Put everything into perspective to what you are doing to your car, if you have big 'bling' wheels, is saving a few lbs from the brakes to make up for your heavy wheels worth it? Are you going to drive your car to the point to notice a difference anyway? Is running on unproven/tested products worth it to you? -all questions you should consider when coming to a decision.

 

[TURBO2GO]

Nice post again Billy. I am running stock 17" forged alu wheels. Not interested in bling, only weight savings.

As far as the Racing Brake reply, may I just point out some flaws:

The calipers are not rotating mass, only unsprung weight. Two totally different things. Rotational mass can be multiplied, but 4-5X is questionable. The weight savings on a two-piece rotor is at the center of the rotating mass which affects braking and acceleration much less than the weight of the tire for example which is out closer to the edge of the rotating mass. He is guessing 8-9 pounds on the stock caliper, I don't think factory calipers weigh that much. There is some savings here no doubt but that 35-40 of static weight.... there is no way. There is roughly 9 pounds of weight savings on the rotors alone, for all 4 wheels. If we are going to do this static weight conversion, since they are rotational mass, then my guess for the center mounted rotors is a useful 15-16 pounds. Add another 6 pounds for 2 calipers (as the calipers are only avialable for the front), and you have a total of 20-21 pounds with the static to rotational mass conversion... and 15 of *actual* weight reduction, MAYBE... depending on stock caliper weight.

They don't offer a rear system, and the suggestion is to just get their OE upgrade for the rear and then mix that with the front aluminum caliper which has totally different characteristics than the factory caliper. Does this sound like a tested and engineered 4-wheel system? It doesn't to me.

I went back and read a ton of brake threads till my brain started to smoke... and then talked to a few guys again that I trust. I am not expert enough to start experimenting with pads and brake bias controllers which is what these guys told me to do after getting a good front setup. Forget it.

I will either just get a 4-caliper kit or I am keeping stock calipers and stock rotor sizes. Billy's thread a couple of years ago with those hats coming clean off the discs with the picture is enough to deter me from getting RB two-piece rotors for track use. I am not going to wrap my 100K investment around guard rail to save 15 pounds. Yes the risk may be small, but I just didn't like those pictures. I know a few members here ran well (vintageracerNYC) with the RB OE upgrade, but for me personally... I didn't get any sort of satisfactory answer from RB on your disaster. And so I sold my OE upgrade kit.

 

[john@johnhudakracing]

Dave,

All things considered, the stock rotors with some fluids, proper pads, and maybe ducts will likely be fine for you at this point. I think you would be amazed at just how far that unsexiness can go. All things considered, the person in the best position to know is still usually your "instructor"... or to defer to Billy's point... someone senior that looks like he might know something about going actually fast. (this is why all entrants should have lap times on their name tags) :smile:

Further, as Billy stated, you can get your rotors (hell I take my flywheels) turned on a lathe in some forsaken back alley shop without worry. Fussing over corner weights at this point isn't worth the effort. Their is no chase in obsessing over infinitesimal engineering improvements or chasing down the last 10th at this point. You have better things to be spending your money on right now- like replacing those 615's.

For my S2000 I use the re-branded stockie rotors from Pep Boys ($60) but yes, the NSX ones cost a little more.

BTW, welcome back to the NSX track forum this year. You can also just leave your Visa at the door. :wink:

Hope you have a great, fun summer.

- John

 

[stuntman]

Nice post again Billy. I am running stock 17" forged alu wheels. Not interested in bling, only weight savings.

As far as the Racing Brake reply, may I just point out some flaws:

The calipers are not rotating mass, only unsprung weight. Two totally different things. Rotational mass can be multiplied, but 4-5X is questionable. The weight savings on a two-piece rotor is at the center of the rotating mass which affects braking and acceleration much less than the weight of the tire for example which is out closer to the edge of the rotating mass. He is guessing 8-9 pounds on the stock caliper, I don't think factory calipers weigh that much. There is some savings here no doubt but that 35-40 of static weight.... there is no way. There is roughly 9 pounds of weight savings on the rotors alone, for all 4 wheels. If we are going to do this static weight conversion, since they are rotational mass, then my guess for the center mounted rotors is a useful 15-16 pounds. Add another 6 pounds for 2 calipers (as the calipers are only avialable for the front), and you have a total of 20-21 pounds with the static to rotational mass conversion... and 15 of *actual* weight reduction, MAYBE... depending on stock caliper weight.

They don't offer a rear system, and the suggestion is to just get their OE upgrade for the rear and then mix that with the front aluminum caliper which has totally different characteristics than the factory caliper. Does this sound like a tested and engineered 4-wheel system? It doesn't to me.

I went back and read a ton of brake threads till my brain started to smoke... and then talked to a few guys again that I trust. I am not expert enough to start experimenting with pads and brake bias controllers which is what these guys told me to do after getting a good front setup. Forget it.

I will either just get a 4-caliper kit or I am keeping stock calipers and stock rotor sizes. Billy's thread a couple of years ago with those hats coming clean off the discs with the picture is enough to deter me from getting RB two-piece rotors for track use. I am not going to wrap my 100K investment around guard rail to save 15 pounds. Yes the risk may be small, but I just didn't like those pictures. I know a few members here ran well (vintageracerNYC) with the RB OE upgrade, but for me personally... I didn't get any sort of satisfactory answer from RB on your disaster. And so I sold my OE upgrade kit.

I'm aware of the differences between unsprung and sprung weight - if you implied otherwise. It is widely-held that 1lb of unsprung weight = 5,6,7,8,10lbs of sprung weight:

http://www.dsmtuners.com/forums/handling-tech/245249-unsprung-weight-vs-sprung-weight-hp.html

Obviously just because people believe something dosn't make it true.

Even if you went with a BBK up front only, I could give you a good starting point recommendation for front-rear pads, so it wont take hundreds of dollars in pads and tons of track days to have it figured out. Regardless, for your intentions, I recommend staying with the stock rotors (turned or new) with better pads.

All things considered, the person in the best position to know is still usually your "instructor"... or to defer to Billy's point... someone senior that looks like he might know something about going actually fast. (this is why all entrants should have lap times on their name tags) :smile:

So "Johnny Trans Am" with the ITA-Super B spec C 1980's Turbocharged Trans Am that weighs 1,800lbs and has 800hp on 385 width racing slicks with 1 year under his belt and barely turns some fast times is the best person to learn from?

I agree with everything else u said.

 

[CL65 Captain]

Dave,

If you are still doing HPDEs in the novice or intermediate group, don't worry your brakes will have plenty of time to cool down when you get stuck behind the a**hole at the front of the train that won't point anyone by. :biggrin:

 

[2slow2speed]

Hmm..

Isn't Turbo2Go's car Supercharged?

If so his car will probably carry a lot more speed in the straight than a stock NSX, doubt that the stock NSX brakes would be able to handle the abuse, unless he has some serious ducting going on. Running on non R-compounds tires aggreviates the problem as well.

Just my 2cents.