View Single Post
      05-30-2012, 02:49 PM   #35
dogbone's Avatar

Drives: '09 E90 M3 - IB
Join Date: Feb 2012
Location: 93 million miles from the Sun

iTrader: (1)

Garage List
2009 BMW E92 M3  [0.00]
2009 BMW E90 M3  [0.00]
Originally Posted by kartracer12 View Post
Is it necessary to run the ST BBK on the rear with these cars? Are you really getting that much more stopping power in the rear over the OEM brakes? Would it cause an unbalance if you just went with front ST BBK?

I understand doing it for the appearance.
I bought a BBK (not ST) for all four corners for my car, but due to some odd circumstances, the rear calipers had to be installed later, so I was able to experience the car at the track with just the front BBK, and then later with all 4 corners.

Here's my experiences:

-Going from 4 corners stock calipers to BBK in front, stock in back: MASSIVE difference. Cannot be overstated. Shaking steering wheel mostly gone, shuddering mostly gone, fade gone. The car would nose dive quite a bit because the front braking power was so dominant. That would get a bit weird because you could feel the rear tires weren't helping much in your braking efforts. Stopping mostly with 2 front tires can get weird if the road has problems like bumps or debris. You really want the rear tires doing some legitimate work. (I have been on stock suspension which also doesn't help----although that's changing soon).

-Going from front-only BBK to all 4 corners BBK. Subtle but noticeable difference. Shaking steering wheel completely gone, shuddering completely gone. The braking is smooth under all circumstances, it actually grabs your attention because previously you were constantly fighting these issues, and now they're gone and you can concentrate on something else while driving. The car doesn't nose dive as hard. It plants itself better. You feel more solid. (Hoping new suspension will help this even more.)

I change between street and race pads before/after events. I think this is critical to an all-around enjoyment on and off the track. However, putting rear BBK means doubling the number of pads that need to be changed. I tried running my DS2500 race pads in the rear all the time------squealllllllllll. I hate sounding like a bus stopping on the streets, plus it's harder on your rotors. So, if you're changing out pads, more calipers = more work. It does look great though!

So, in the end, is it MORE stopping power? It's a bit more. But what I would say is that is more STABLE and predictable stopping power because all four corners are working more evenly together.