Pulsing brakes

[Ryss]

Could it be disk runout? Does the frequency increase with road speed? Try a DTI on the face of the disks.
Did you clean the hub faces properly when it was assembled?
2 Part disks (if applicable) can also generate runout if the bell is distorted or the fixing faces between rotor and bell are not perfectly clean.

If the pulsing is related to road speed I'd check for misalignment before forking out for new hydraulic parts at random.

Well done Donnie. With that sort of run out the freq of pulsing much change as speed increases. It's, as is often the case, a question of degree. In other words the frequency increases but in will be "less" noticeable the harder you pushes on the brakes.

[newsh]

Bell mounting face thickness is 8mm

[willg54]

Newsh, another one for you!

Could you measure the drop height from the hub/bell mating face to the inner brake surface?

So far i have mine at:
Bell thickness - 11mm
Drop height from inner bell to brake surface - 49mm
disc currently at 30mm thickness

[willg54]

correct me if im wrong:

S8 disc drop height from wheel face to inner brake surface is 60mm which is currently the same as what I have.

the only difference i can tell is they're only 8mm thick where as mine are 11 so the disc will sit 3mm further in-board. Currently, mine aren't dead centre so I think these could actually bring them back to being perfect!

If they don't fit, im sure someone here will need some anyway and I'll have to try another method! Going to get them from camskill.co.uk after reading this http://www.s2forum.com/forum/showthr...ighlight=323mm

[newsh]

Yep, 60mm.

I measure 61mm with the disc face down on a flat surface but I'm sure that's down to the rust on the inner edge where the pad doesn't sweep.

[willg54]

Well i've got the S8 discs from camskill and they seem to measure up as a good replacement for the Movit discs.

The brake surface might be 1mm wider and the disc centre line will be 2-3mm further in-board. But as the current disc doesnt sit centre and with a bit of shimming we'll be all sorted

Moment of truth tomorrow night!

[willg54]

The new discs have solved it! I'm so happy!

For future info, the S8 disc works on the 993 calipers. I had to shim the caliper in by 2mm, probably could have done with 3mm but 2 is all I could manage.

I've now developed a tiny bit of rubbing on the caliper to wheel spokes, ill pick some 5mm spacers up in the morning and we'll be sorted!

I'd like to say a big thanks to everyone who helped with this. Couldn't have finished this car without your help!

Sent from my HTC Desire using Tapatalk 2