I am new here and I have been doin some research on two-piece rotors for my ride and a ran across a few unique designs. I am no brake expert but I do know upgrading your brakes is important when racing

Stoptech has this "Aero" design that allows air to flow between the rotor:


RacingBrake has this "center-mount" design which alows air to flow from both inboard side and outboard side:


These photos were just taken directly off their site, but I want to hear your opinions on this..thanks

 

J Ritt...?

 

These designs look more like reasonable engineering design pumped up with good marketing. STech shows a fuzzy little graph w/ suspicious sounding competitor codes like "B" and "W" (i wonder who they refer to )

RacingBrake shows no data

As a test engineer I can tell you that testing such design for airflow or cooling would be very difficult and expensive ESPECIALLY if you want the data to stand up to scrutiny and give meaningful results. I can assume that as a reputable company Stoptech most certainly ran a test - but I'd still wonder at the accuracy of such a test. And not because I don't trust them - because I know how hard it would be if that was my job.

RacingBrake offers no data other than subjective terms like 'better' and 'more'.

For racing you need better brakes - especially for the non-Brembo cars which have Maxima brakes on the front -

The hard part is to figure out what is enough for YOU and YOUR racing w/out spending unnecessarily.

Of course if you like the bling and have $$$$$$ just get the biggest *** drilled and slotted 15" 8 piston brakes you can find!!

 

infantsam,
Our numbers are absolutely real, and there's nothing pumped up about it. Our Engineering Mgr. has 30 yrs. experience building racecars and brake systems. He isn't some hack that doesn't know how to run a controlled test situation. Our off-the-shelf brake systems are constantly winning professioal races (including endurance races).

http://8.7.96.35/company_info/news.shtml

Do some reading on the technical page of our website if you want to see how deeply we probe into these issues:

http://8.7.96.35/tech_info/tech_white_papers.shtml

 

J Ritt, How much do the Aero Rotors weigh in comparison to the stock rotors on the Bremo's?

 

Read the press release bud...

"The AeroRotor DRK is 2.5 pounds lighter per front rotor assembly and more than 2.75 pounds lighter per rear rotor than the stock rotors, creating a total reduction of 10.5 lbs total weight savings versus the stock rotors."

 

Jeff
I've read the whole site - several times - but I've only scanned since the upgrade to see whats new. Looks good btw....kudos to the designer. I am aware that you win races and I was not calling anyone a hack.

What I said was in response to the posters question in regards to the 'airflow' claims made on your and RacingBrakes website. My skepticism is as an engineer - not a consumer. In other words if I was trying to run a test that measured airflow through a rotor I would be very challenged by the difficulty of the test set up and any data it produced and I'd be very interested to see how it was done (proprietary I am sure). I'm imagining little pitot tubes inside the vanes - or some sort of sealed enclosure around the perimeter....

Also - isn't the actual cooling rate what is really imortant. Higher airflow doesn't guarantee more heat transfer - make the flow extremely high but laminar and heat transfer goes down. Some amount of turbulence is necessary - it's your engineers job to try and figure that out although trial and error would seem to be more effective than analysis.

It wasn't a slam - just my annoying engineering 2 cents.

 

you can measure 'air flow' based on the temperature differences if you run the same friction/speed tests with different vent designs.

change a design, see the delta. better or worse.. that would tell you if your vents are working properly... baseline volumetric numbers would be harder to come by. i.e. CFM flow thru the vents while rotating.. but that's not really the point here... for Stoptech, they're looking the best way to cool the rotor thru extended run times...

thats how I would test it.. being an engineer as well.

 

I understand Infantsam...no worries, and thanks on the web comment.

My Eng. Mgr. built a flow bench and ran the tests. We've talked about the matter on a number of occasions. In addition to the oodles of simulations, yes there was quite a bit of trial and error. As an Engineer, you definitely know the value of real-world testing vs. theory. That's why we test our kits (which many of our competitors don't do). Now that we've designed over 400 applications, we usually get within a very close range of what we see as ideal on the first pass. Testing is now more for refinement and dialing than anything...not like the early days of our company. Have you ever seen our field testing?
http://zeckhausen.com/Testing_Brakes.htm

Cooling rate is indeed critical. We've done quite a bit of testing with everything from VW Bugs to Daytona Prototypes (some of which are currently running our rotors in Rolex Series). We've gotten tons of data through the racing venues. There's definitely a fine balance between cooling rates, heat transfer, etc. If the rotor cools too fast, then you're seeing big swings in temps between brake zones which can lead to premature cracking. Obviously, it depends on the car, how much air it draws through the rotor, how quickly it decelerates, etc. We've found a great design that isn't perfect in all situations, but it's the best we've seen under most conditions.

We've also taken our analysis to the direction and shape of slots or drill holes on the face of the rotor, the shape of the vane as it "blends" into the face of the rotor, etc. For example, we don't drill and slot our rotors, because we've found that heat transfer is inhibited if too much material is removed in certain areas of the rotor face. Also, drill hole patterns and their orientation to the vanes, etc. is critical. It's important to have the heat generated at the rotor face 'flow' properly into the vane structure so it can be dissipated.

Well, I'm babbling at this point, but you get the idea. Great pains have been taken to evaluate our products on paper and in the real-world. We're not a company that makes bold claims of "increases stopping power by X%. Smart people know that is a bunch of crap, and my Eng. Mgr. would string me up if he ever heard that nonsense come out of my mouth! We are definitely doing our homework.

 

Glad you brought the 2002(?) Zechausen test again as I've always wondered if Zechausen used the same pad compounds on the OEM-Brembo-Stoptech setups?

There is not mention of pads anywhere in the test. Which would be the most critical element of the whole ordeal (after tires maybe).

brake test without mention of brake pads.... find it laughable.

 

StopTech

 

Nano,
I'm glad you've made it your personal mission to chime in with something negative to say on every post that StopTech is involved with. What exactly is your issue with our organizaion? Have you ever even tried our brakes?

As for laughable...where exactly is all of the technical info, discussion, and support from all of the other brake manufacturers?

I can find out about the pads...not a problem.

 

See it as you will...

I just find it odd that I am the one who needs to point out to you the importance of brake pads in brake system performance.

 

Brake pad, what's a brake pad? Yes, thank you so much for enlightening me on the importance of brake pads.

Somewhere in the world right now, there's an argument starting...an argument based on mis-information and gross generalizations...where the participants know very little about the actual subject matter at-hand. You better hurry up and find it, or you'll miss your chance to chime in with your inflammatory $0.02.

 

wow sarcasm... that's impressive.

yeah, I am the one who has issues with gross generalization and missinformation... gotta love stuff like "most of our competitors don't test their products" ..... "most of our competitors brakes don't fit"...... "our tests demonstrate that our products are better than the competitors" ... "we sell race brakes unlike watered down version of our competitors"...



so to reiterate(since you took it so badly as to resort to personal attacks).... it's perfectly fine for you that there is no mention whatsoever to brakepad compounds/brand in a braking test?

 

Nano does have a valid point, although I don't quite agree with his tone of voice. To truly test two different brake systems and compare them objectively, everything except for the brake components themselves should remain the same. This includes wheels, tires, and even brake pads.

I read too many tests where they use different combination of cars, tires, and pads, then claim to say one brake system is superior over another. I'd love to see a more objective test that is done with more control, meaning the cars are the same down to the type of pad they are running, and the only difference between the set up are the brake rotors and calipers. Then again, if the brake manufacturer is selling pads as part of their complete set up like Endless, it's a different story, but for companies like Stoptech and Brembo who don't push their own pads as much, using the same brand/type of pads would make for a much more objective comparison. At least, I think that's the point Nano was trying to make.

 

ok, so which would be better the racing brake 2 piece, or the stoptech 2 piece, and heck, I will throw one more in there, what about the dba 5000 series 2 piece for the OEM brembos.
I am converting from non-brembo to brembo and already have the OEM brembo calipers for front and rear, the goodridge steel braided lines, and the project mu b force pads also for front and rear, all I need now is the rotors. I have decided no to spend the extra money on 2 piece rears as weight savings off rears isnt as important and the rears arent too involved in braking and need to be changed less often. For the front i am still debating whether to go with 1 piece or 2 piece and whether to go with stoptech, dba, or racingbrake. All 2 piece brands are like within 60 bucks of each so $ isnt really a factor.

 

wow, brought back from the dead. since this is back i'd still like to see what brake pads were used for that zeckhausen test.

 

Good luck.