Track Day (none competitive) Rotor Options (Iron) solid disc?

[mitch32]

As title, besides the drilled options from FCP Euro (and the lifetime warranty) is there any cheap solid disc options for our cars?

[SYT_Shadow]

I would never run solid iron rotors on something this heavy. They will fry the bearings even faster than the OEM setup, that has pins to separate the rotor from the hat.

I believe there are cheap rotors out there that are one-piece, but they do not belong on track

[M3SQRD]

If you plan on sticking with the oem brake setup, why not invest in a two-piece rotor setup thru FCPeuro? After two rotor replacement you’ve invested basically the same amount as two stock rotor replacements. As SYT_shaddow said, don’t run cheap (cost and material) solid face rotors on the track. If it’s a DD and you need brakes to get you to work and back, I can see the argument for running cheap rotors (I personally never would on a car with > 400 hp/torque stock) but never for track. The brakes are the most valuable safety systems you have on the race track. Don’t mess with it.

[mitch32]

Originally Posted by M3SQRD

If you plan on sticking with the oem brake setup, why not invest in a two-piece rotor setup thru FCPeuro? After two rotor replacement you’ve invested basically the same amount as two stock rotor replacements. As SYT_shaddow said, don’t run cheap (cost and material) solid face rotors on the track. If it’s a DD and you need brakes to get you to work and back, I can see the argument for running cheap rotors (I personally never would on a car with > 400 ho/torque stock) but never for track. The brakes are the most valuable system you have on the race track. Don’t mess with it.

While I agree, the issue is these rotors thin down so fast and then overheat and because of the drilled holes I’m worried. I have shattered a cross drilled rotor on the way home after the track in another car I had when I hit a puddle, it wasn’t catastrophic but the noise was real bad still made it home. The bearing argument is a good one. I have personally not had issues with oem rotors on this car at all, the m2 and Supra guys at the track a frequent have all switched to solid one piece non-drilled. You will get coning and taper wear this is a biproduct of a gooseneck or conventional rotor vs a 2-piece this goes without saying. The Supra and m2 guys both have a lot thicker rotors then us so their thermal capacity is a lot higher, so the bearing argument definetly comes into play. If BMW or any company had rotors not for 1400$ that were not cross drilled that be optimal, the issue when tracking is I burn through rotors pretty quickly (5-12 days), I only have a couple track days on the f82 platform but definitely took off about 0.2mm in one track day which is about 8 track days before the rotors need to be changed if you do the math.

[M3SQRD]

Originally Posted by mitch32

While I agree, the issue is these rotors thin down so fast and then overheat and because of the drilled holes I’m worried. I have shattered a cross drilled rotor on the way home after the track in another car I had when I hit a puddle, it wasn’t catastrophic but the noise was real bad still made it home. The bearing argument is a good one. I have personally not had issues with oem rotors on this car at all, the m2 and Supra guys at the track a frequent have all switched to solid one piece non-drilled. You will get coning and taper wear this is a biproduct of a gooseneck or conventional rotor vs a 2-piece this goes without saying. The Supra and m2 guys both have a lot thicker rotors then us so their thermal capacity is a lot higher, so the bearing argument definetly comes into play. If BMW or any company had rotors not for 1400$ that were not cross drilled that be optimal, the issue when tracking is I burn through rotors pretty quickly (5-12 days), I only have a couple track days on the f82 platform but definitely took off about 0.2mm in one track day which is about 8 track days before the rotors need to be changed if you do the math.

What track brake pad are you using? Do you brake early or over slow the car? I’m not familiar with the Supra but the M2C brakes have larger and thicker rotors but that alone doesn’t make it a better braking system. I’d never run the M2C brake setup even with Girodisc rotors but that’s me.

If you’re worried about cross drilled rotors (which btw there are two types - cast in vs actual drilled, BMW holes are cast in), you need to closely inspect them before and after track sessions AND bring at a minimum a new set of spare front rotors. Cracks grow slowly from the thru holes and take a long time before they reach a free edge. I used to use up the rotor thickness before having a crack grow to an edge. If you’re going thru rotors with five days on track then you need either a new brake setup or a maximized oem setup. Personally, I’d go with an Essex/AP Racing or BW/Alcon F & R brake kit. StopTech and Paragon (their own caliper or a Alcon mono6/mono4 caliper) kits are a little easier on the budget. You do get what you pay for when it comes to braking systems. BTW, I’d stay away from StopTech until they address their stocking/distribution issues. If you stick with the stock setup go with 2-piece slotted/j-hook rotors, air deflectors, steel domed pistons, etc. plus track pads that are easier on the brake rotor (e.g., PFC 11, Cobalt XR1/XR2, CT XP12/XP20). But please do not run cheap rotors, especially cheap materials, because they can fracture just like drilled rotors.

[SYT_Shadow]

it sounds like you have a brake performance issue, but the solution is to go in the opposite direction and get better hardware

Girodisc rotors are expensive, but worth every penny with massively increased durability. That, air deflectors (BW sells a good kit), good pads and potentially some domed pistons etc for your calipers make a big difference

You will see some E36/E46 racecars running 'blanks' as rotors, but those cars weigh very little and have engines that are massively less capable than the S55. You can do it with a light car and little power, but not on a F M3/4