Brake pads with different friction coefficient **Update**

[glasgow]

Having a problem of over brake rear tyres. They lock before the front.

One of the suggestions is to change the brake pads and get more grippy pads at the front.

Car is 2003, standard brake. My understanding is:

A) Rear: The Lucas part number is: GDB472 "Ford Scorpio 91 on"

(as in pic the rear brake caliper has "cn3 208 0659/7" written on it).

B) Front: Can't read the writing . Can anyone advice about the type of the front caliper and pads please?

 

Regards

Ahmed

 

 

[DJ.]

I have an S3 with standard brakes, and I am sure it was over braked at the rear.

I posted this thread:

http://www.lotus7.club/forum/techtalk/brake-pad-advice-please-1

I followed the advice from Richard Price in post #5, and there was a signicicant improvement in braking efficiency and the fronts lock first.

Duncan

[glasgow]

Thank you Duncan for the useful thread.

So:

- Front: Mintex MGB533 M1144

- Rear: http://www.caterhamparts.co.uk/product.php?id_product=668

I do understand I need to upgrade the front pads, but why would  I need to change the rear pads? Could I just keep the current standard rear pads unchanged? 

Any suggestion where to buy the Mintex MGB533 M1144. Google search suggested Merlin Motors and Qwix.co.uk

[David Brown]

Ahmed, I've fitted 1144 pads to the front and find the balance to be fine. 

David

[glasgow]

And as for 80 grit for the rotors, any guide of how "heavy" should I press with the grit please?

[PhilR]

I believe the front brakes are Girling type 14. I have just purchased a front set of Mintes 1144 model 533a pads from Rally Design £44 delivered.

 

I will email you a link.

 

Phil

[Wrightpayne]

I have mintex fronts and std rears and am happy with the set up. Fronts lock up first.

Ian

[DJ.]

If you just change the fronts to 1144, the balance will move to the front and the fronts will lock first.

However, as stated in the thread, the 1144 grip so much better than the standard pads the rears will not be doing much braking before the fronts lock.

Richard Price suggested the uprated rears to get the balance nearer the ideal situation where all four brakes work hard, but the fronts lock first for stability.

Having fitted the suggested combination, I can confirm that the fronts lock first even with uprated rears. You will get more balanced brakes by changing both sets, but just doing the front won't be dangerous, you just won't stop quite as quickly.

[glasgow]

Is this applicable to any seven? Are there other factors that affects rear brake. For example tyre type/width, driver/passenger weight, car setup and corner weighting? Should the pads change be done one stage at a time to see how the rear brake reacts?

[glasgow]

Update:

Replaced front pads with Mintex M1144, used grit 80 on the discs and did the bedding in.The only difference is the brake pedal feels softer (and brake is now squeaky) BUT still rear brake locks first. 

If I replace my standard rear pads with the uprated ones, my understanding the uprated rear brake pads would make the rear brake even "stronger" and won't help in my issue-correct?

Any suggestions please?

Thank you

[Gloucestershire AR]

Not an expert but 'not necessarily'.

My understanding, in a non-technical way (always dangerous...), is that standard brake pads are quite 'soft'. Initially they grip very well - this gives drivers of all abilities the best braking for emergencies. The typical emergency will be a one-off 25 to 0 mph stop or slowing down on a motorway when following too close, playing with the radio and realising the car in front is braking hard... Most modern cars are fitted with ABS but most motorists never brake hard enough to activate it.

However, drive on a race track or up and down mountain passes and these pads will overheat, leading to less braking effect and, ultimately, brake failure.

Competition pads are 'harder' - that is their initial grip may actually be a bit lower but as they (very quickly) heat up, so their efficiency improves. They are less likely to overheat and will give you very good braking from higher speeds.

So, 1144s on the back may actually result in less initial lock-up but better braking overall. But it all depends...

I'm sure an expert will be along in a minute and explain why that is not/may not be the case!

Andy

[Mankee]

Where's that guru Richard Price when you need him?!

Do you run the same size wheels and tyres front and rear or wider rears? It might be worth trying 1144s on the back as well. Better braking on the back may help with pedal modulation and "pull" the back end down during hard braking instead of pitching all the weight onto the nose and lifting the rear, so you get more grip and less lockup.

[DJ.]

Just changing the fronts to 1144 should move the bias forwards assuming the rear pads are standard. I am surprised the rears are locking first still.

 

Is it possible the rear pads aren't standard?

[glasgow]

Do you run the same size wheels and tyres front and rear or wider rears?

 

Tried with two sets of tyres 1st one is 205 all around and the second is 185 front and 205 rear. Same problem of rear lock with both sets of tyres.

 

Is it possible the rear pads aren't standard?

I assume they are standard. How would I know?

[john milner]

Could there be air in the front of the braking circuit?