There are alternatives. I had this issue with my MB rotors which are 2 piece from factory. They do not sell rings only so I had them made, 3x cheaper than buying OEM.

 

How does this enhanced cooling due to a vented rotor compare to a 2.5" rear brake duct?

 

IMO, moving air through the rotor is much more effective at cooling than moving air on the outside of one rotor face. Also, cooling one rotor face will cause a temp difference vs the outside and could lead to warping. Ducting is really meant to push air inside a vented rotor.

 

I understand that logic. But it would be good to see some data. Also, cooling just one side of a solid rotor will not cause uneven cooling. Cast iron has a fairly low thermal resistance and a solid rotor has a much higher cross-sectional area internally for heat transfer to the other side as compared to a vented rotor.

 

wat?

 

I meant to say cross-sectional area. Whoops, lol.

Take a solid and a vented rotor and slice each down to two discs. See which one has more surface area connecting one half to the other...

 

Yep.. I wouldn't worry too much about getting replacement rotors these days, as you can probably get a set made one off worst case, and it won't be too expensive. I'll be honest, I've been considering a custom rear setup, but I'd likely just prefer going with their option at this point if I kept the OEM rear caliper.

Any word back on rotor life and how they lasted on the test car? Either way, definitely nice to see more options for our car.

 

Tester going back out to VIR this weekend, I will get an update on Monday/Tuesday.

 

The mounting flange thickness is 6mm on the hat & rotor each so 12mm total X 10 bolts. We should have plenty of shear resistance.
Also, we have spring clips on the bolts limiting movement between each other further reducing stress.

My tester didnt have temperature measurements, but simply noted that rear brakes are now usable and provide braking force where before they quickly got too hot. Experience is worth more than raw data sometimes. Although I am an engineer and would like the raw data too.

 

We have these in stock currently. 8 Sets delivered, we should be seeing some rear world reviews soon.

Again, we don't feel a bigger rotor is needed as we have proved that with our Front BBK. Combined with a rear Vented rotor, we feel you will get consistent braking on both sides of the car.

Our tester noted how much the rear brakes helped his Front BBK. My theory is that the rears slowly start to overheat as they are not vented and the front BBK starts to take more and more brake force on. Eventually the rears completely fade and fronts take on close to 100% braking force and then start to go.

We feel having a front BBK coupled with a vented rear rotor should provide consistent braking and lower wear for track cars up to 500 HP and maybe even more.

Thanks to all that purchased in the the launch buy.