Wilwood BBK?

[s8ilver]

Anyone have any experience or thoughts on the BBKs from Wilwood? Brakes are usually the first system I get to my liking when I get a car, and a supercharged M Roadster definitely needs to stop safely before anything else.

I know they make two different 6-piston setups for the Z: 13.06" and 14.00" (requiring 18" wheels). They also do a 4 piston rear kit, which would look great but probably unnecessary.

Overkill? Stock brakes with upgraded pads a better option? I did a Stoptech BBK on a buddy's S4 and the results were pretty amazing, like tear-your-face-off amazing. On my S8, the massive OEM 4-piston Brembo calipers are plenty. I just did dimpled rotors (Adam's Rotors) with some Street Performance pads and she stops on a dime.

Any thoughts much appreciated.

[PbFut]

BBK feel like they provide big improvement over OEM because the original setup was not likely tuned for maximum performance. You can get very close to the same performance out of an OEM Z3M system as you can BBKs on the market. With proper pad choice, and front cooling if on the track, you will be a few thou$and ahead by not giving into the marketing hype of the brake companies. If it's a look you want, buy whatever your eye fancies.

[s8ilver]

With proper pad choice, and front cooling if on the track, you will be a few thou$and ahead by not giving into the marketing hype of the brake companies.

Good point; if BBKs use OEM hydraulics (and they usually always do), there's no reason not to be able to get more out of the OEM system. We added a few bucks worth of Home Depot cooling to our LeMons race car, and it made a world of difference. It wasn't pretty, but surely got the job done. I'm usually a form follows function kind of guy, but I have to admit that a BBK on a car as good looking as a Z wouldn't be a sin in my book. Thanks!

[Bcar]

Its all about heat. The OE system can be upgraded w/ pads, fluid, SS lines, and COOLING (if you're tracking it). At that point, you're going to need more/better rubber to out-brake the brakes. The PO on my car put a Brembo BBK on the coupe and it is amazing, but ive yet to hit limit of the brakes, tires are the weak link and the system will go into ABS before full pedal pressure is reached.

Wilwood makes a nice system though, as does rallyroad if you want to save even more coin.

[s8ilver]

At that point, you're going to need more/better rubber to out-brake the brakes. The PO on my car put a Brembo BBK on the coupe and it is amazing, but ive yet to hit limit of the brakes, tires are the weak link and the system will go into ABS before full pedal pressure is reached.

I'm planning bigger rubber next spring (235F, 285R) to help put that power down. I'll sort braking along the way. Thanks for the advice. Ditching the OEM 17" rims will be the big decision. I have my eye on the Apex PS-7 18x8.5 & 18x10.5. To my knowledge, 265 is about as wide as I should go on stock rears.

[Zoupe6]

Just curious, is your brake booster vacuum line plugged with your SC set-up, or was it rerouted somewhere with vacuum? Although minor, if left unattached it can take some of the initial bite out of your braking.

[s8ilver]

Just curious, is your brake booster vacuum line plugged with your SC set-up, or was it rerouted somewhere with vacuum? Although minor, if left unattached it can take some of the initial bite out of your braking.

Great question. I have yet to see the car in person (local shop did a very thorough PPI), but I believe install was done exactly per VF manual. I'll see if I can download for plumbing routing information.

I had planned on running a boost gauge first thing and was going to tap at bypass valve (as recommended by VF Engineering), not at the booster line.

[TurboBimmer]

I don't think that the 'M' needs to go to 18'' wheels.
The rotor diameter is enough to lock the wheels even with R compound tires. The only place I could see improvement is in heat absorption capacity. by going to a thicker rotor and with a caliper to fit, better pads, and maybe cooling ducts if required.

Just for comparison, I won't use my Z3 since it is stock, but my E30 has Wilwood rotors that have a diameter slightly smaller than the stock M ones (12.2 mine vs 12.4'' MC) and the thickness of the rotor is (1.2'' mine vs 1.1'' MC) so a bit thicker and no ducting. The width of the rotors is significant but the heat absorption is very good. I never had brake fade with that setup.

If I was tracking a MC, I would first try with race pads, and if not enough, some ducting, before going with a BBK.

[s8ilver]

I don't think that the 'M' needs to go to 18'' wheels.

Need? Probably not. I do love the Roadstars. The clearcoat is cracking and the rears have some minor rash. I've always wanted to refinish my own wheels; perhaps I just found my first winter project.

Want? Absolutely. The 14" (355mm) Wilwoods require 18" wheels, but the 13.06" (331) do not. My stock 345 rotors on my Audi look massive under 18" wheels.

Decisions!

[TurboBimmer]

Need? Probably not. I do love the Roadstars. The clearcoat is cracking and the rears have some minor rash. I've always wanted to refinish my own wheels; perhaps I just found my first winter project.

Want? Absolutely. The 14" (355mm) Wilwoods require 18" wheels, but the 13.06" (331) do not. My stock 345 rotors on my Audi look massive under 18" wheels.

Decisions!

If you just 'want it', 18 and BBK is the way to go, they look nice!
But if you're tracking the car seriously, having bigger wheels and too big brakes will only add unsprung weight that will affect suspension, acceleration and braking. Acceleration may be cancelled by the supercharger, and braking by the BBK, but it's a guess.

[PbFut]

All good points. One other I did not see. BBK modulation is easier at oem limit level relative to smaller system because you are not on ragged edge of system ability prior to look up. ABS covers most of that issue but still you can feel things better with BBK. That being said. With street rubber non issue. Race rubber above applies. But again, skill of driver will play in. I feel I am better than average track driver but still do not beleive i would gain much if any net time. There are plenty other improvement to apply that 2 to 6 grand.

[Bcar]

There are plenty other improvement to apply that 2 to 6 grand.

This.
But, I do love the way the BBK looks and feels as PbFut said. Im never bottoming the pedal out. But if you've already got a SC, some type of brake mod is required IMO.

18s for sure look better, but if I was to do it all over again, Id go 18 front and 19 rear.
As a ref point, im running 235/285 PSSs and it is still not enough rubber for the BBK. I havent had the car to a highspeed/high brake track like Road America yet, but even there with good pads/fluid on street rubber it would be fine. Put slicks or R compound tires and you might need more brake, but only after trying cooling.

[s8ilver]

18s for sure look better, but if I was to do it all over again, Id go 18 front and 19 rear.

Interesting. Any photos of an M with 18F & 19R? I can't imagine the ride would be very nice on the street.

I'm not a serious track driver, but I like to know the slow matches the go. I haven't even decided if the M will see a track, and if it does it'd be a few times a year. My home track is brutal on brakes. It took us three LeMons races to sort brake fade on our race car...ended up with some Porterfield endurance pads and cooling ducting on OEM rotors and calipers. The car is a factory intercooled turbo Volvo 240 wagon. Massive 4 piston calipers and two brake hoses per front caliper from the factory. A soccer mom car full of kids and gear does get pretty heavy I guess!

[CMM3]

you should talk to Lee at Massive Brakes or email is a better way to communicate with him lee@massive.com
He provided me with a kit F & R for my 2001 Z3M
same 4 pot radial AP racing calipers 1.5 & 1.625" pistons front and rear = same brake pads.
fully floating 332x32mm rotor 13"x1.25 front & rear
Massive brackets, & hats retaining rear parking brake.
And they clear my 17' Apex wheels

[s8ilver]

you should talk to Lee at Massive Brakes or email is a better way to communicate with him lee@massive.com
He provided me with a kit F & R for my 2001 Z3M
same 4 pot radial AP racing calipers 1.5 & 1.625" pistons front and rear = same brake pads.
fully floating 332x32mm rotor 13"x1.25 front & rear
Massive brackets, & hats retaining rear parking brake.
And they clear my 17' Apex wheels

So, essentially these F&R, but AP instead of Wilwood?

http://www.massivebrakes.com/brake-s...p=e36_rear_332

Very cool! I like the idea of keeping the 17" option, and only one type of pad to replace seems very practical. Do yours fit behind the OEM 17x7.5 fronts, or did you have to (and/or want to) go wider with the Apex wheels? I was looking at 18x9 and 18x10.5 (wanted as much rubber as possible in the rear due to S/C), but would consider 17x9 and 17x10.5.

Another question regarding wheel/tire setups. Let's take 17" for example. My go to tire for many years have been the Continental DW. They come in a 235/45 and 235/50 front and 275/40 and 285/40 rear. The 235/50 and 285/40 are both about 5% larger than stock diameter. Any issues here? The car is going on H&R/Bilstein Sport springs/dampers. So essentially suspension brings car down about an inch (perhaps 1.25") and larger rubber would bring it up just over 1/2".

From what I can tell, rolling diameters are as follows. I know manufacturers differ in actual sizes, but the straight math approach is what I used.

OEM 245/40-17: 24.71"
OEM 225/45-17: 24.97"

CDW 285/40-17: 25.94" (+5.0%)
CDW 235/50-17: 26.25" (+5.1%)

[TurboBimmer]

Try to keep your diameter around 25'', max 25.2''.
At 26'' you have more chances to rub, especially if you lower the car, and by having 5% more diameter, you loose 2.5% torque/hp to the ground, so, slower acceleration.