Z4 MC Rotora Brakes and 4 seconds off best time!

Originally Posted by brad otoupalik

We have data acquisition, but it was 4 years ago, and I would be hard pressed to find it. However, my customers in the two turbo cars we run have no budget. They would put on anything that worked better (short of spending the 20K on the Brembo GTR for club racing). They both had Brembo on previous cars and one on this chassis also. They are both more than happy with the change to Rotora, and they gained time on the track.

They have set track records at every track they go to, that is proof enough for me.


thanks
Brad

You don't have to sell me... I am already sold on a caliper only kit and based on this the Rotora is on the top of my list! You could have easily told us we need a big rotor and made a more expensive kit but instead you are only selling us what we actually need which is a caliper. Props to you! I had John Dimoff from Raven Performance (also a successful BMW club racer) as my driving instructor this summer and we had a talk at length about brakes. His advice was that the stock CSL rotor was big enough and the caliper and cooling where the only limiting factors in the brake system.

John is a great guy! We work with Raven quite a bit. Good people!

Originally Posted by brad otoupalik

John is a great guy! We work with Raven quite a bit. Good people!

They really are a great group of guys! The first time I took a drive down to Raven John spent more then 2 hours showing us everything in the shop even though they were swamped with work... really a cool move on his part! Although a tough driving instructor I learned a ton from the guy. I can't wait to do a school at Mosport with them this summer.

Any idea on pricing for the 6 piston caliper kit?

email me at brad@evosport.com and I can put something together!

If fade is a problem run brake cooling ducts to the rotors. It's cheap and effective.

Here is good turn but turn guide of ACS but Billy Johnson.

http://www.motoiq.com/MagazineArticl...eo-Inside.aspx

Originally Posted by deknight

The pad sizes are significantly bigger than stock. The fronts are about 1.5 times bigger than stock fronts and rears twice as big as stock rears. With a bigger pad it takes less effort to stop the rotor than a smaller pad so less fade. The pad type can play a big role in fade as well. The stocks pads will fade much more than a track pad.

-Actually it still takes the same amount of effort to stop the rotor (physics), you just don't feel it through the pedal because of changes in the piston pressure, caliper stiffness, etc. The larger pad area makes it possible to extract a lot more energy from the rotor in a shorter period of time, which usually equates to a shorter stopping distance (limited by tire traction). The down side is that this will create more heat that the stock system in a shorter period of time. Running a higher-temp pad will help to prevent pad fade, but fluid fade could still be an issue since the rotors will have to cool more than with stock calipers/pads.

Originally Posted by deknight

I am curious about the weight differance over stock. When i was looking into my setup i was asking Palantirion for his opinion on a good setup. He loves his stoptech 4 pot front and rear (i drove it and i thought i was good too, just went another direction) but he said that his stoptech front rotors (which are bigger than stock 355 i believe) are 10 lbs. lighter than stock per rotor. Unless it was a typo is that because StopTech uses a differant compound than Racing Brake?

Just looked up the weight of the StopTech, they are light at 15.25 lbs (355x32). So they are alot lighter. Does the stock weight 19 lbs? If so that would be nearly 10 lbs. for both on weight savings.

-Unfortunately I don't have the individual component weight for that mod, just the total after I added everything up. I recall that the ST front rotors (355s) were each 10lbs lighter than stock, and the rears (much larger than stock) were 3lbs heavier. I didn't mind this tradeoff since it shifts weight balance rearward. And I LOVE the brake balance, having a more "square" setup.

I think a picture of the caliper kit installed on the rotors would go a VERY long way to pique my interest as well.

Well I cannot give you a picture of the caliper kit installed on a Z4 coupe, but I just got these pics today from Rotora on the new 6P caliper.

This is the "race" version:

• RF601 (6-Piston Caliper): Forged, Titanium Piston Inserts, Anti-Knockback Springs, Natural Anodize Finish
• Billet Aluminum Caliper Bracket: 7075-T6
• H9 Carbon-Metal Endurance Pads
• Stainless Steel Brake Lines: DOT Compliant

And here will be the "street" version of this kit.

• RF601 (6-Piston Caliper): Forged (red or metallic blue), with dust-boot
• Billet Aluminum Caliper Bracket: 7075-T6
• H2 Ceramic Street Pad
• Stainless Steel Brake Lines: DOT Compliant

Here are some pics of the e46 M3 caliper kits being installed on one of the race cars:







Here is a pic of one of our cars that runs the caliper only kit:



Thanks
brad

LOL, Brad, when I first glanced at the first pic above I thought you were posting StopTech's Trophy calipers (also 6-piston, anodized finish with red lettering)! I'm so used to equating Rotora with aqua (is there an official name for Rotor's blue-green color?) that it took me a second to see what it was. You should also make the race calipers available with aqua-colored Rotora lettering (if you don't already do it) for better brand recognition.

Brad - thanks for the great pics. Is there a "race" version of the 4 piston calipers as well with the anti-knockback springs and titanium pistons?

Originally Posted by Palantirion

LOL, Brad, when I first glanced at the first pic above I thought you were posting StopTech's Trophy calipers (also 6-piston, anodized finish with red lettering)! I'm so used to equating Rotora with aqua (is there an official name for Rotor's blue-green color?) that it took me a second to see what it was. You should also make the race calipers available with aqua-colored Rotora lettering (if you don't already do it) for better brand recognition.

The street challenge kit is the same caliper, just without all the bells and whistles, and it comes in the trademark "metallic blue" also.

Originally Posted by pal

Brad - thanks for the great pics. Is there a "race" version of the 4 piston calipers as well with the anti-knockback springs and titanium pistons?

Yes, the rear kits are 4P and I will know more about the potential fitments for the front caliper only kits soon.

thanks
Brad

Are the street kits available in the Race coloring?

No. Unfortunately, the only way to get the race looking caliper, is with that kit.

Can they build that caliper for "street" usage?

I have been too lazy to post pics of the caliper only kit on my car. Will do so soon. It desperately needs a wash!

Originally Posted by Getssum96

Can they build that caliper for "street" usage?

Yes, the street challenge is the SAME caliper body, just different options. So you can get that caliper for the street.

I will check to see if things can be swapped around.

thanks
Brad

Thanks Brad. Look forward to the 4 pot "race" kit information as well.

On the note of springs for countering knockback - is'nt that bad for a street car as the pads will constantly be in touch with the rotor?

Originally Posted by Getssum96

Can they build that caliper for "street" usage?

You don't want that. Race calipers REQUIRE rebuild every year and it's big $$$. Most race calipers do not come with dust boot to prevent brake dust from entering into the piston, since it is EXPECTED to be rebuilt every year (some of the more extreme, endurance type race cars rebuild the caliper after every RACE). Street calipers are great for looks on the street and excellent for DE and some club level racing...Race calipers are good for one thing. Race.

Hey Brad (OP) - hah, I was just researching these new kits that Brad posted on BF only to find your thread here. Cool stuff, and nice vid! I hope I just rebuilt my stock calipers for the last time and am excited about these kits. You going to BW with SV on 12/20?

Not sure if Brad will be there, but Rune will be. He will be sporting the new race Super Challenge on his M3. You cannot miss it - it is Ti Silver with a Porsche GT3 RS Orange cage and interior. You can see the kit up close and talk to him about his set-up.

Feel free to call me if you have any questions. I am thinking since you already have Comp package, the caliper kit would be about a perfect fit for you!

thanks
Brad

Originally Posted by Hit_Apex

Hey Brad (OP) - hah, I was just researching these new kits that Brad posted on BF only to find your thread here. Cool stuff, and nice vid! I hope I just rebuilt my stock calipers for the last time and am excited about these kits. You going to BW with SV on 12/20?

i was signed up for the 19th with the Buttonwillow Driving Clinic but they will not run CW13 so i probably will got to SV on the 21st rather than the 20th, since the Monday event, just added, will have less cars.

Here are some pics of the brakes finally!


Front


Rear


Both

Originally Posted by The HACK

There's nothing tricky to brake rotors. You can't really use a different "compound" per se. It's cast grey iron, or you have to go to the tricky carbon/ceramic mixture to save weight on the rotor (über expensive).

Sorry for jumping in here, but my life would be substantially easier if this were true! Actually, a lot goes into selecting grades of iron, graphite flake size, alloying elements, thermal post-processing, etc., when it comes to iron rotor design. I won't even go into plate thickness, air gap, vane layout and construction, heat dams and more. Having said that, BMW tends to choose better iron than others. Not necessarily track-ready, but certainly good enough for a lot of folks. As for carbon-ceramic, there are currently far fewer options to choose from. Well, for now at least.

Originally Posted by The HACK

You don't want that. Race calipers REQUIRE rebuild every year and it's big $$$. Most race calipers do not come with dust boot to prevent brake dust from entering into the piston, since it is EXPECTED to be rebuilt every year (some of the more extreme, endurance type race cars rebuild the caliper after every RACE). Street calipers are great for looks on the street and excellent for DE and some club level racing...Race calipers are good for one thing. Race.

Agreed 100%! Although some street calipers are up to a lot more track duty than their brethren of only 5-7 years ago. Seal technology has improved significantly for the manufacturers who specialize in top-level motorsports (Formula 1, NASCAR, WRC, LeMans prototypes, FIA GT, etc.). The seals used in certain street calipers today are made of the same materials as race-only calipers of just a few years ago. Once production numbers increased, costs came down just enough to justify the upgrade.

Originally Posted by Palantirion

-Actually it still takes the same amount of effort to stop the rotor (physics), you just don't feel it through the pedal because of changes in the piston pressure, caliper stiffness, etc. The larger pad area makes it possible to extract a lot more energy from the rotor in a shorter period of time, which usually equates to a shorter stopping distance (limited by tire traction). The down side is that this will create more heat that the stock system in a shorter period of time. Running a higher-temp pad will help to prevent pad fade, but fluid fade could still be an issue since the rotors will have to cool more than with stock calipers/pads.

The size of the pad does not determine stopping distances (assuming the pad is not run past its maximum operating temperature). However, a smaller pad will get hotter than a larger pad for the same braking effort. In other words, the increase in surface area reduces the energy density on the face of the pad, keeping temperatures lower. If a pad is too small, it will always run hotter, eventually reducing its effectiveness (fades too early) and its life (accelerated pad wear). If a pad is too large, it will take longer to heat up when cold and could suffer from taper issues if not carried in a well-designed, multi-piston caliper.

Chris