Stoptech Article Regarding Rear Brake Upgrades

[rzm3]

Originally Posted by AP Racing - Chris_B

Not looking to argue, but Turner ran Alcon's front and rear at Daytona this year.

http://www.turnermotorsport.com/html...010/daytona24/

When they were running StopTech, AP Racing was making the rear rotors for the ST calipers. Rahal-Letterman uses AP front and rear in ALMS GT2. The FIA GT4 cars in Europe also come with AP's front and rear.

You just won't see OE sliders on the rear in professional racing, at least not at the top levels. Not that it translates directly to street vehicles, but the difference is noticeable or they wouldn't do it. Brake companies do not give much product away, so teams with limited sponsorship may not have a choice. AP Racing does not sponsor any race team anywhere, so all their customers are buying the equipment.

What I do know is that when people go for the rear upgrade, there is nothing but positive feedback regarding performance. It is almost always related to pedal feel and trail braking. Many upgrades, like the AP system for the E9x M3, are designed as a F/R system and should be used together, not separately, to get the best performance out of either.

Chris

1. I am talking about the M3 here. The link you provide is an M6.

2. I surely understand that the Continental Challenge is not one of the fastest or most technically sophisticated race leagues out there -- it is not meant to be. But it is a league relevant to people with street-going M3s because those cars being raced at a professional level are still mechanically very similar to the street going M3s... many of them were striped and modified from street cars. This is the whole point of bringing up these cars to this discussion.

It doesn't matter that the ALMS M3 GT2 has this or that because Rahal-Letterman's M3s are so remotely different vs. street production cars. The M3 GT2 is wider, lighter, suspension completely remounted, race version P65 engine, sequential gearbox, significant aerodynamic effects, etc. (the only thing it shares with the street M3 is the ugly chrome grilles)

3. I am not arguing that rear BBK upgrades do not offer performance or other advantages. I have a rear BBK myself. What I am trying to say is that for those who want the best bang for the buck, a front BBK (designed to work with stock rears) may be good enough in terms of being able to produce consistent stopping power and heat management.

Cheers.

[rzm3]

Originally Posted by HP Autowerks

I think if you were to look into the rule book, they are not allow to change the rear brakes, otherwise all the teams will look to get rid of the floating caliper and add a bigger rotor.

There is also added thermo capacity with an aftermarket BBK. In the case of the Stoptech the rear rotor size is 355 x 32 where as the oem is only 350 x 24. Not to mention more pad selection and quick changes without removing the caliper.

1. Could you point out where in the rule book says "front BBK" only?
http://www.grand-am.com/assets/Sport...lesforweb1.pdf

2. Do you have data showing OE rear kits have thermal management issues?

3. Let's assume that the rule does not allow rear BBK for the moment, but aren't the M3s running just fine and winning podiums in a professional racing series?

[HP Autosport]

1. Could you point out where in the rule book says "front BBK" only?
http://www.grand-am.com/assets/Sport...lesforweb1.pdf


7-2.1 GRAND-AM may allow a brake upgrade for specific models. If allowed, only one two-piece (split into two halves) caliper of aluminum alloy with a maximum of four pistons and two pads per wheel permitted.

may allow...front BBK, but not rear.

2. Do you have data showing OE rear kits have thermal management issues?

I didn't mention there was anything wrong with the oem rear brakes. However, there are some advantages to be gained with an aftermarket BBK. Some of those already mentioned by another member.

3. Let's assume that the rule does not allow rear BBK for the moment, but aren't the M3s running just fine and winning podiums in a professional racing series?

Sure.