Wednesday, 20 April 2016

Folembray Prep - Brakes

I can't quite believe it's been a year since going on a three day round trip to St Quentin, France with a day in the middle at Folembray circuit... Well it's not 'exactly' been a year... but I've made the decision to go again with the same group at the end of next week (Early May Bank Holiday weekend).

Whilst at Folembray last year I had recently fitted some ZZR tyres and some Nitron shocks... I found on the blat to the circuit there was a bit of under-steer, and at the circuit pretty major under-steer which I tried to dial out with tyre pressure and damping adjustments; but meant I also had to adopt a slightly different driving style to accommodate... Turns out after having the car flat floored that the suspension setup was terrible, borderline un-driveable, so on reflection there was no real wonder why I was struggling for front end grip.

So now having everything pretty much sorted in terms of setup, I'm hoping to be able to improve on the lap time (so long as it's dry!)  and with that in mind, I've a few things that will (hopefully) help me achieve this goal. 

New Brake Pads, Fluid Change and Bleed
When I had the car flat floored by Rob at RatRace Motorsport, he 'sold me a seed' about brake pads, which I must say had been on my mind for a while... I just couldn't shake his suggestion that he had some 'special compound' pads which he'd developed over the years that vastly improve braking distance and feel over the standard pads! 

Having noticed towards the back end of last year that the brake pedal was a bit spongy and certainly required a lot more effort to stop the car-which meant my grey matter had buckled; and a week or so ago, I decided that life wouldn't be living without these new pads.  So off to RatRace it was!

On arrival I was greeted by Rob and his Rottweiler (Aston), who pretty looked pretty gutted to see me again :-(
Robs Rottweiler (Aston) realising I'm back again!
Robs Rottweiler (Aston) realising I'm back again!
Onto the brakes...  Firstly, as much of the old brake fluid was removed from the reservoir using a an hand extractor pump.
Old brake fluid removed from reservoir
Old brake fluid removed from reservoir
The fluid was replaced with a new higher performance DOT 4 called Castrol React Performance.  This should be more resistant to heat and will reduce any fade that I may experience.
Castrol React Performance DOT 4 fluid going back in
Castrol React Performance DOT 4 fluid going back in
With the new DOT 4 fluid in the reservoir, the rear bleed valve was plugged with the bleed catch tank, I jumped (not literally) into the drivers seat and pumped the brake pedal until it was firm... Rob then released the bleed nipple, tightened it back, I re-pumped and so on until the new fluid was through and we were happy with the fluid colour and pedal feel.
Rear brakes ready for bleeding
Rear brakes ready for bleeding
With the rear brakes bled the old pads were removed and even though I've only done around 3500 miles the rears were cracked and had about 25%... Which is probably due to quite a few track laps... The new pads on the rear are visibly different with two sections to aid cooling which will help.
New pads (top) vs Old pads (bottom)
New pads (top) vs Old pads (bottom)
The new pads had some copper slip applied to the outer sections to stop squeaking and were then fitted.  Some more copper slip was put on the wheel nut threads, the rear wheels were re-fitted and that was the rears done.
New rear pads fitted
New rear pads fitted
Now onto the front pads...  These were a little more complicated to bleed and replace as to get access to the retaining bolts, the calliper on the nearside needed removal from the hub.
Front brake calliper was removed - note Aston's eyes in the background
Front brake calliper was removed - note Aston's eyes in the background
I can't remember the offside calliper being removed, and my photos seem to confirm that it wasn't removed.  The same process as the rears though, more brake fluid, and the system flushing through.
Front brakes ready for bleeding
Front brakes ready for bleeding
New pads (right) old pads left... They seem very similar, but the old front pads were in much better condition than the rears... However, there was still signs of some cracking where they have potentially been overheated, so was good to replace - the new pad material is also softer too.
New vs old front pads - not much difference in appearance
New vs old front pads - not much difference in appearance
New front pads fitted...  Everything was torqued up, the brake fluid topped up and the wheels replaced.  Job done!
New front pads fitted
New front pads fitted
With the new pads fitted and brakes bled with new fluid it was time to pay the bill and head off home... It was chucking down with rain so wasn't an ideal opportunity to test the new brakes but, the pedal feel was back to how it was when I first got the car (I guess this is down to the fluid and bleed)... Apparently the new pads will really help, so I look forward to trying them out at Folembray... I'm just praying to the weather gods that it'll be dry!

However - I think next time I'll bleed the brakes myself, as I found the following video on YouTube which makes it look very easy to do on your own... Not only that I'm sure I've got an easy bleed brake kit hiding in my garage somewhere!


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