RacingBrake BBK Rotor Sizes! 380mm? 360mm? 347mm?

DallasBoosted · 09-21-2012, 07:17 PM

Warren at RacingBrake would like to know what size BBK most of you would prefer. This would be a front-axle BBK that uses the RB 4-piston calipers and a custom bracket with RB's 2-piece rotors.

Stock 335i size rotors are 347mmx30mm. You're all familiar with the great 2 piece replacement rotors RB makes in that size.

E90 M3 rotors are 360mm. Warren says he can make a kit for the 335i that uses this rotor size. This should still fit under most 18" wheels.

The third option would be a 380mm rotor. This is a huge 15" rotor that will likely require 19" wheels to clear.

Let me know your thoughts and I'll pass them on to Warren @ RB.

(Disclaimer: I do not work at nor am I affiliated with RB in any way. Just helping the guy out.)

CJ421 · 09-21-2012, 07:41 PM

If I were buying a BBK, it would have to fit 18" wheels. So probably 355-360mm.

will.c · 09-21-2012, 08:56 PM

I think the stock rotors are large enough. A BBK that fits over stock rotors to distribute the braking force evenly on the entire contact patch would get my vote. With the stock single piston, the most of the braking seems to get done around the midline of the rotor width, not utilizing the inner and outer brim to their fullest. I also assume that these would clear 17" wheels, which is a big plus IMO.

HP Autosport · 09-27-2012, 06:46 PM

On a 335i, even with extensive mods, 355x32 or 35mm will be more than enough with a 4 or 6 piston caliper.

380mm with a 4 piston will easily fit inside of an 18" wheel.

DallasBoosted · 09-27-2012, 07:39 PM

Quote:

Originally Posted by HP Autowerks

On a 335i, even with extensive mods, 355x32 or 35mm will be more than enough with a 4 or 6 piston caliper.

380mm with a 4 piston will easily fit inside of an 18" wheel.

Okay but 355mm isn't one of the choices - it's stock size, 360mm size (M3 size with a 335-spec hat so it'll fit on our hub) or 380mm. It'd be 30mm width like the stock rotors.

HP Autosport · 09-27-2012, 08:18 PM

Quote:

Originally Posted by DallasBoosted

Okay but 355mm isn't one of the choices - it's stock size, 360mm size (M3 size with a 335-spec hat so it'll fit on our hub) or 380mm. It'd be 30mm width like the stock rotors.

347 or 360 will also do.

Chriskm3 · 03-03-2013, 12:10 AM

How about a rear bbk for a e92 m3

kenneth · 03-03-2013, 12:46 AM

Could you tell him that his calipers need to accomodate more common pad shapes. Their current calipers which work on the stock size RB 2-piece rotors (347mm) have limited pad choices due to their pad shape.

I would have bought those calipers were their pad shape more common.

View Poll Results: What size rotors would you like Racing Brake to make for their 335i BBK kits?
Stock size 347mm.	4	20.00%
Stock M3 size 360mm.	7	35.00%
380mm.	9	45.00%
Voters: 20. You may not vote on this poll

09-21-2012, 07:17 PM	#1
DallasBoosted Captain 41 Rep 864 Posts Drives: '08 E92 335i Join Date: Apr 2012 Location: Dallas iTrader: (3) Garage List 2008 BMW 335i [10.00]	RacingBrake BBK Rotor Sizes! 380mm? 360mm? 347mm? Warren at RacingBrake would like to know what size BBK most of you would prefer. This would be a front-axle BBK that uses the RB 4-piston calipers and a custom bracket with RB's 2-piece rotors. Stock 335i size rotors are 347mmx30mm. You're all familiar with the great 2 piece replacement rotors RB makes in that size. E90 M3 rotors are 360mm. Warren says he can make a kit for the 335i that uses this rotor size. This should still fit under most 18" wheels. The third option would be a 380mm rotor. This is a huge 15" rotor that will likely require 19" wheels to clear. Let me know your thoughts and I'll pass them on to Warren @ RB. (Disclaimer: I do not work at nor am I affiliated with RB in any way. Just helping the guy out.) Last edited by DallasBoosted; 09-21-2012 at 07:22 PM..
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09-21-2012, 07:41 PM	#2
CJ421 Brigadier General 2061 Rep 4,266 Posts Drives: BMW G80 M3 Join Date: Feb 2011 Location: PA, USA iTrader: (1) Garage List 2024 BMW M3 Sedan [9.67]	If I were buying a BBK, it would have to fit 18" wheels. So probably 355-360mm. __________________ 2024 BMW M3 Sedan Frozen Pure Grey II/Fjord Blue, 6MT Past: 2021 Z4 M40i Frozen Grey II/Black Alcantara \| 2017 F30 340i Mineral Gray/Coral Red, 6MT \| 2011 E92 335i Le Mans Blue/Black, 6MT
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09-21-2012, 08:56 PM	#3
will.c Captain 139 Rep 638 Posts Drives: E46M Join Date: Mar 2011 Location: Central Jersey iTrader: (5)	I think the stock rotors are large enough. A BBK that fits over stock rotors to distribute the braking force evenly on the entire contact patch would get my vote. With the stock single piston, the most of the braking seems to get done around the midline of the rotor width, not utilizing the inner and outer brim to their fullest. I also assume that these would clear 17" wheels, which is a big plus IMO.
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09-27-2012, 06:46 PM	#4
HP Autosport Supreme Allied Commander 4212 Rep 56,228 Posts Drives: F80 M3 Join Date: Mar 2007 Location: Santa Barbara, AP, Brembo, GIAC, Koni, Ohlins, Performance Friction, www.hpautosport.com iTrader: (36)	On a 335i, even with extensive mods, 355x32 or 35mm will be more than enough with a 4 or 6 piston caliper. 380mm with a 4 piston will easily fit inside of an 18" wheel.
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03-03-2013, 12:10 AM	#7
Chriskm3 Colonel 60 Rep 2,184 Posts Drives: M3 Join Date: Jul 2012 Location: Toronto iTrader: (4)	How about a rear bbk for a e92 m3 __________________ Vf supercharger + tune/H&R coils/ Akra evolution exhaust/Volk te37/ Rs-3 tires/ Brembos /TIal BOV/ OSS blacked out headlights/LUX v3/Led taillights/ Challenge Front lip/ P3 vent gauge/ F10 m5 shift mob/Matte black front grills/ And a funky air fresher
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03-03-2013, 12:46 AM	#8
kenneth Major General 127 Rep 8,745 Posts Drives: 335i Sedan Join Date: Mar 2007 Location: Montreal iTrader: (16)	Could you tell him that his calipers need to accomodate more common pad shapes. Their current calipers which work on the stock size RB 2-piece rotors (347mm) have limited pad choices due to their pad shape. I would have bought those calipers were their pad shape more common. __________________ SB, Terra, 6MT. Only a few mods here and there.....nothing extreme!
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