Brake Bias and Differential Changes for road cars.

You get looking at race cars long enough and start wondering....

Are brake bias setting and Differential settings able to be changed on a roadcar/sports car. I mean if you wanted to alter the brake bias on your Corvette or Mustang, is it even possible. Just not somethings you hear a lot of track guys talking about. Not sure if its determined by the ABS module or not.

Likewise for the Differential settings. Can you alter the amount Locking and Open differential on deceleration and acceleration?

I come from a karting background(shifter) so brake bias changes are a common change. Obviously not differential since they don't use a diff. Maybe on uber expensive high performance sports cars/hyper cars they have the ability alter both brake bias and differential settings but I can't point to an example off the top of my head.

Just curious to hear others opinions

Hi Blair, both the adjustments you mention are common on higher end race cars. An adjustable brake bias normally requires a proper pedal box with independent front and rear master cylinders however on non-abs brake systems with a common rear circuit you can incorporate a pressure reducing valve to get some level of brake bias adjustment (only reduction though, not increase). The majority of modern cars are obviously equipped with ABS now and the ABS unit can control brake bias but of course this isn't usually something the end user can control.

While a factory differential won't offer any adjustment, there are a range of aftermarket LSD centres which are tuneable. These are available traditionally in 1 way, 1.5 way and 2 way which defines whether the diff will lock under acceleration only (1 way), acceleration and braking (2 way), or predominantly accel but with a lesser amount of locking under braking (1.5 way). In the mainstream LSD centres the actual ramp angle is fixed though. The other adjustment that has a huge impact on the LSD performance and general handling balance is the preload on the clutch plates and the number of active plates.

Sorry to hijack the OP but wanted to place a question since abs and its affect on brake bias . If a factory equipped abs unit (or even aftermarket) is malfunctioning on a vehicle what will happen then ? What I mean is ok the abs won't engage when needed but how will the brake bias be affected during track day or race event ? Will it be affected by if it is the pump or a sensor that is malfunctioning?