34 replies to this topic

[Winstar]

With the talk of brake bias and the vx being better with more bias at the rear why don't people just fit a bigger diameter disk at the rear?

the calipers are axially mounted not radially so you can't fit bigger disks, it's easier to fit higher friction pads at the rear.

[Steve B]

With the talk of brake bias and the vx being better with more bias at the rear why don't people just fit a bigger diameter disk at the rear?

the calipers are axially mounted not radially so you can't fit bigger disks, it's easier to fit higher friction pads at the rear.

I see, I've not looked at mine at all yet.

I assumed when people talked about fitting bigger discs they were talking about all round as surely if the car benefits for more rear bias (which doesn't suprise me - MR2s all have bigger rear discs) fitting bigger fronts just makes things worse?

I think from whats been said here maybe a set of Elise parts alloy belled diss just on the rear maybe a good idea.

[bazzio]

sbs protrack pads, standard discs!!

[2-20]

Edited: wrong place

Edited by 2-20, 12 February 2017 - 06:30 PM.

[D-DAWG83]

Had a braking revelation myself on my trackday on the 21st Jan. Iv got RC5+ pads all round, with 4pots and ali bells all round, and have never been happy with the brakes. Iv now discovered that there is very little feel from the pads/discs, but my god is the perfomance there.if admit to not having driven a standard car set up, but i was totally shocked at how hard i could hit the brakes without locking up. I did have RC6 pads in the rear, but swapped them to the 5+'s as i could feel the rear just starting to lock up on turn in.

[Aerodynamic]

I have bigger front discs and Mintex 1155 all around and I think balance is fine, I wouldn't like to have more rear biased. Br, Per

Edited by Aerodynamic, 13 February 2017 - 08:04 AM.

[2-20]

Brake bias is also dépendant to wheel sizes. With 16 inches fwd wheels you have more fwd brake bias

[JG]

I haven't found a car that stops better than a vx with four pots

[fiveoclock]

I haven't found a car that stops better than a vx with four pots

A VX without them and proper braking technique

[Tonie Pettersson]

Brake bias is also dépendant to wheel sizes. With 16 inches fwd wheels you have more fwd brake bias

Can you elaborate? Due to weight difference?

[2-20]

Law of physics. What make you brake is the force between the road and the tyre at the contact patch. For a similar amount of braking torque, if your lever arm is smaller (wheel+tyre radius) then the force at the contact patch is higher.

[Tonie Pettersson]

Law of physics. What make you brake is the force between the road and the tyre at the contact patch. For a similar amount of braking torque, if your lever arm is smaller (wheel+tyre radius) then the force at the contact patch is higher.

 

Thanks .

[james_ly]

Law of physics. What make you brake is the force between the road and the tyre at the contact patch. For a similar amount of braking torque, if your lever arm is smaller (wheel+tyre radius) then the force at the contact patch is higher.

 

Hmm I can't get my head around this? Surely the braking force is between the pad and disc. If wheel size was relevant it would have an effect when accelerating too?  

[navx]

  Hmm I can't get my head around this? Surely the braking force is between the pad and disc. If wheel size was relevant it would have an effect when accelerating too?  

It does affect acceleration if you change size of driven wheels. Principle of moments.

[2-20]

Braking is the result of à chain of actions It starts by the force applied by your foot on the pedal and it ends at the contact patch of the tyre which see shear stresses. One of the force of this chain is between the pads and the discs, but you realize that before that there was foot force transformed into pressure in the hydraulic system and after that you have the disk radius and coefficient of friction to create a braking torque. The braking torque created by the disk and pads is transformed into force at tyre contact patch level. The longer the lever arm (wheel + tyre radius) the lesser the force at the contact patch.