Hi everyone,
I thought I'd share this with you all, but current StopTech owners and prospective buyers will be particularly interested in this one...Here is a copy of a press release from our website, and some pics. In short, our rotors went the full 25 hour race distance at Thunderhill (560 laps for this car), plus an extra 100 laps of practice and qualifying. The brake system on the Bullet car is made from the same exact components that are on our street kits for the Z. Obviously, the part sizing is slightly different, but our racing and street kits are made from the same pieces. I thought you guys might enjoy seeing what your kits are capable of.

StopTech Rotors Enable a Class Win and Go the Full 25 Hours of Thunderhill

Torrance, CA… It took five drivers and only one set of StopTech AeroRotors® for Bullet Performance of Costa Mesa to win their class and place 8th overall in the ultimate endurance race - the 25-Hours of Thunderhill. Seventy-five race cars, including top teams from around the country, took on the challenge of the race dubbed the “new king of enduros.”

Bullet Performance ran StopTech’s World Challenge 322x28mm brake upgrade on their #56 1996 BMW 328is. At the 12-hour mark, the team was leading their class and 7th overall. “The StopTech brake system performed great the entire race with negligible brake fade. We were able to continuously brake deep into turns,” said Chris Welch, one of the five drivers of the Bullet team and co-owner of Bullet Performance. “It was unbelievable that not once did we have to change our rotors or pads during the 25 hours of non-stop racing, and this reliability allowed us to save time and increase our lead.” According to Mickey Miller, driver and co-owner, they completed 560 laps in the race and 100 laps of practice and qualifying on the same StopTech rotors.

After starting the race at 11:00am on Saturday, Bullet Performance took the checkered flag the next day at 12:00pm. StopTech’s front-only World Challenge brake upgrade kit includes two-piece floating directional AeroRotors® with directional AeroHatstm, ST-40 4-piston calipers with patented bolt-in bridge, and StopTech stainless steel brake lines. The team ran Hawk HT-10 track pads in the front and had a third of the pad remaining after the race. The low pad wear evident in this grueling race was a direct result of StopTech's superior AeroRotor design. The tremendous air flow through the patented internal vanes and directional hats allowed the rotors to stay cool enough to keep pad wear to a minimum.

The World Challenge brake upgrade is designed for 55 minute sprint races and the rotor is smaller than the standard StopTech 332x32mm BMW E36/E46 3-Series brake upgrade. Despite the use of the smaller components, the brakes performed flawlessly during the much longer 25-hour enduro event. According to Steve Ruiz, StopTech engineering manager, “this successful result once again shows the benefits of the StopTech AeroRotor® and AeroHat™ design in racing applications.”

 

Nice...another proof why Stoptech is one of the best in the market.. Two thumbs up

 

Glad I went with Stoptech...

 

Congrats! Quick question, I noticed you have slotted rotors on there instead of drilled, why? Are they better I was always under the impression that drilled was better.

 

2 different functions... tho Im not sure what the function of drilled is other than appearance; slotted routes hot gases from under the pad to let it clamp down. I think drilled is sposed to be for cooling and less weight; but rotors absorb heat into their weight; less wouldnt be real good for fade.

now J Ritt can come along and correct all of that information with he truth

 

Mr. J Ritt

Your information has sold me. Any additional thoughts of a Four wheel 335mm brake combo for the 350Z?

I'll keep in touch with Jeff@performance ..

Good show

Cheers Amy -

 

question, I know it was an endurance race, but is this normal??

 

Slotted rotors scrape the pads clean of deposition as they pass over and slighty fall into the slots. Drilled rotors are for ballers and stockcar drivers from the '50s. Rotors were first drilled in the early days of motor racing because the brake pad compounds of the day would outgas and create a thin layer of gas between the pad and rotor which had the same effect as a puck on an air-hockey table. The rotors were drilled to allow the outgassing to dissipate and not remain trapped between the pad and rotor surface.

BTW, for all of the people who actually cross-drill their rotors after the fact instead of buying rotors with holes made as a part of the casting process, the cracks in the StopTech rotor are nothing compared to what ghetto-*** cross-drilled rotors would look like after a few sessions on the track.

 

See Droid's answer below (thanks Droid). StopTech ALWAYS recommends slotted rotors for track driving. Drilled rotors are more prone to cracking. We only rerecommend drilled rotors if you plan on driving on the street. Another tidbit...look closely at the slots...they do not go all the way to the edge of the rotor (you will see that on some comptetitive products). Slots that go all the way to the edge of the rotor are also more prone to cracking.

As Droid said, the idea is to allow gasses to escape, and to create more bite on the pad as it crosses the edge of the slot or drilled hole. Heat transfer and strength are fundamental to a good rotor design. If you look at the slots, the are actually slanted in the opposite direction of the internal vanes...in a sort of cross hatch pattern. This is done to provide strength in the rotor, which does deform when it really heats up and is squeezed by the caliper. If you were to slot the rotor in the same direction as the vanes...would you put the slot above a vane, or situate it between vanes? If you put it in between the vanes, you would be taking material out of the rotor without any supporting material underneath of it...which would weaken the structure. If you put it above a vane, you would be taking material away from the heat transfer mechanism. Imagine the rotor from a cross section view...the internal vane would look sort of like a T where it connects to the inner rotor face. Now imagine if you removed the chunk of the line where the vertical and horizontal lines of that T meet. If you tried to transfer heat from the horizontal line into the vertical line, it would only trickle in from the two little points where the horiz. lines were still touching the vertical line. Now think about how easy it would be to move heat with all of the lines more or less intact. The cooling air pumping through the rotor would more easily come into contact with the heat if it was distributed throughout the vanes and faces of the rotor. Sorry if this is confusing...it would be much easier to see with a drawing! Hopefully that makes sense.
The StopTech 2 wheel kits should be more than sufficient for performance purposes. The 4 wheel kit will handle any and everything you could ever hope to throw at it. Most people choose the 4 wheel kit for looks, better rear pad and rotor wear. It is the ultimate brake setup for the Z, period.
As Droid said, that is absolutely normal. If you look closely, you'll see more than just that one crack you circled. Rotors are a consumable item. They will eventually crack. A proper design that promotes cooling and good metallurgy will delay the cracking. That's what you're seeing here. The heat generated by the brakes in endurance racing is tremendous. An inferior rotor would have died a painful death long before this one did!

 

Nice!

If and when I ever get brakes, they'll definitely be Stoptech.

Gotta support my Torrance people.

 

so why do Porsches come with drilled rotors?? Looks???

 

Yes looks.

 

To dissapate the heat. IIRC the Porsche rotors are cast with the holes. Many of the aftermarket sets are just brembo blanks that are drilled.

 

ok Porsche puts drilled rotors on their high performance cars for looks both drilled/slotted have their pros and cons

 

I've heard it said that Porsche does it for the rain factor which is ridiculous IMO as we all know that water will not remain a liquid for long on scalding hot rotors.