Brakes cause back to slide

[Pursey]

I have notice In some of my cars that under heavy brakeing the back end wants to try and slide round and loose control. Is this being caused by to much brakeing force up front or to much on the rear? I did try 6 up front and 4 on the back and it was a little better.

 

[Famine]

Too little on the rear, usually.

 

[Scaff]

I have notice In some of my cars that under heavy brakeing the back end wants to try and slide round and loose control. Is this being caused by to much brakeing force up front or to much on the rear? I did try 6 up front and 4 on the back and it was a little better.

I'm moving this to the tuning section, as that is the right place for a tuning question.

However in a nut-shell, too much rear brake bias will cause lock-up at the rear and unsettle the car, particularly if you are running low or no ABS.

Click on the tuning guide link in my signature and download the first one, it covers brake balance settings and much more.


Scaff

 

[Novice]

I have notice In some of my cars that under heavy brakeing the back end wants to try and slide round and loose control. Is this being caused by to much brakeing force up front or to much on the rear? I did try 6 up front and 4 on the back and it was a little better.

too much brake force in the rear, assuming you're not locking your brakes. if you do, that's the cause of your problem regardless of brake balance setting.

 

[JCoop]

I agree with Scaff.

The brake bias number (force) to the rear should be less than the fronts.
i.e., too much brake force to the rears will lock them up and allow the rear of the car to skid around; especially in a turn.

 

[cicohipe]

Yeah, it's probably brake force. Alternatively you can add positive toe, rear downforce, or reduce lsd torque to the rear deceleration to get rid of this. Any or all of these will work.