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      03-11-2018, 10:37 PM   #1
kyrix1st
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Brake bias for E92?

Trying to set up brake pads, and I would like to know front-rear brake bias. Does anyone have any number on this?
(I tend to put stronger pads in the rear to neutralize car’s movement on hard braking)
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      03-13-2018, 06:41 PM   #2
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I'm curious to hear more about this because I'm under the assumption that weight transfer is solely tied to the deceleration rate and not to which axle is actually doing the braking. For example, if you redline the car in 1st gear and then let off the gas, you'll still have a ton of weight transfer even though only the rear axle is doing the braking. That means the rear wheels are losing grip and fronts are gaining grip.

If you put better pads in the rear, I think you would get less weight transfer simply because the car won't be able to slow down as quickly. Also, you'd risk getting into the ABS in the rear before you hit threshold braking in the front so you'd never be able to maximize your stopping distance.
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      03-13-2018, 11:54 PM   #3
kyrix1st
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Quote:
Originally Posted by macdude357 View Post
If you put better pads in the rear, I think you would get less weight transfer simply because the car won't be able to slow down as quickly. Also, you'd risk getting into the ABS in the rear before you hit threshold braking in the front so you'd never be able to maximize your stopping distance.
I think if you think in the sense of weight load, the more front is loaded, the more braking force is needed, which at certain point, would be irrational to have too much front bias because front tyres will be more prone to lockup due to accelerated wear. I'm not doing anything crazy though, I feel better with just a touch more rear bias (by feel, around 5~10%.)

It all comes down to driving style I guess. I personally feel much more stable having a bit more rear bias during threshold braking since it is easier to downshift and turn in due to less nose down. I hate loading front tyres and understeering into the corner.
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      03-14-2018, 02:44 AM   #4
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Quote:
Originally Posted by macdude357 View Post
If you put better pads in the rear, I think you would get less weight transfer simply because the car won't be able to slow down as quickly. Also, you'd risk getting into the ABS in the rear before you hit threshold braking in the front so you'd never be able to maximize your stopping distance.
i've read similar things affirming what you're saying... warning against using too aggressive of a pad in the rear. makes sense, because during braking, you're going to transfer weight regardless.
i don't think locking the rears or triggering abs in the rear would be good.

i've seen some companies recommend running the same pads front and rear, and other companies recommending different compounds front and rear. i don't think i've read about anyone recommending a more aggressive pad in the rear than the front to compensate for weight transfer.
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