The standard SBG rotor is the lightest... any lighter and you won't have a performance brake kit though. We can build a brake kit with our 330x20 mm rear rotor ring, which would shed lots of weight, but your car wouldn't stop more than once. Also rotational mass you won't save much here, all the weight is towards the center of the wheel. If you want to save rotational mass, 16" wheels with the lightest tires you can find.

I can weight the rotors but the number would be irrelevant, we've tried smaller rings and they don't have enough mass/cooling to stand up to repeated brake applies on modified cars (especially on track). If you really want to know I'll measure them, but the number you're looking for is not going to help you in any way to build a more "performance" setup.

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I'm at a certain point in auto-x where the last couple of turns (depending on the course setup) I get a bit of fade. It's not detrimental to me to upgrade to a BBK at this point, but if there was weight to be lost in addition to better brake performance, then I would do it. So yes, the weight of the rotors would be nice to know!

 

If you are experiencing fade in auto-x you may just have to change the pad compound and fresh brake fluid.

Many Japanese time attack and touge FD actually use stock brakes (admittedly the larger late model stock brakes) with aftermarket pads to get the bias/abs engagement just right (big brake kits throw this off a bit).

I have used Hawk HP+ for street/auto-x since they have great initial bite and are durable enough for auto-x (though not repeated track lapping).
One venue I race at is a short kart track with a 60-80mph straight into a banked sweeper and another 40-60mph back straight into a tight kink among other features. Even on DOT Rs and 5 competition laps (4 minutes) my stock brakes with Hawk HP+ were fine.

I upgraded to the Willwood 6 piston 14" brake kit (basically for looks) and I can tell you the rotors weigh much more than stock.
You are going to have a hard time gaining thermal capacity of the braking system without increasing the rotating mass.

One way to do so would be to add brake cooling ducts if your class rules allow them. At the very least most classes should allow the R1 front spoiler and brake ducting if you don't already have those 4 factory pieces.

 

Wilwood site does list component weights with the rest of their specs.

For instance here is the specs on the just the 14" (355.6mm) rotor disk my Wilwood kits uses.

https://www.wilwood.com/Rotors/Rotor...no=160-8401-BK

14.5Lbs each, plus the steel hardware and Aluminum hat.

Wilwood lists just the rotor disk for their 12.88" (327mm) kit at 11.9Lbs

https://www.wilwood.com/Rotors/Rotor...o=160-13544-BK

Might give you an idea of about what the Sakebomb Garage components weigh.

 

I too am running the Hawk HP+ pads with the stock system, and running the Motul 660 fluid. But I am probably seeing much higher speeds and a bit harder on the brakes.

Thanks for that info!

 

Nice! Sounds like you have some fun courses.

Another factor I wasn't thinking of is the V8 FD weighs 340lbs more than the 2 rotor in SSM as well. Not huge weight, but 14% more.

 

It sounds like for your application a combination of Of titainium backing plates ( about 8 times more resistant to heat transfer ) and good ducting to air cool the disks before the heat can get to the calipers , should be the ticket ....less fade smaller brakes ..