Shaking steering and pulsing brake pedal under braking

[Lee H]

Bought a secondhand Wilwood Midilite 4 pot brake kit for my Nova and fitted it and getting a major issue when braking that shakes the steering wheel and pulses the brake pedal. I thought it would be the disks being warped so had them skimmed on the lathe by an engineer but the problem still persists.

There is no shaking under acceleration or at speed, just under braking.

Could it be the calipers at fault or is it still likely to be a problem with the disks?

New disks are £150+ so don't want to waste money buying them if it might not solve it.

Cheers

[deanwilko]

do all the pistons move freely on the calipers

[Stuart]

have you bed them in properly? sounds like the transfer layer isnt built up right yet

[Lee H]

They sat slightly proud when I got the calipers so pushed them back in to fit new pads and all went back in ok by hand. Not sure if this is normal as its impossible to push normal caliper pistons back by hand?

[Lee H]

have you bed them in properly? sounds like the transfer layer isnt built up right yet

Not done many miles but its practically impossible to drive, brakes are lethal going on and off all the time lol

[jimbob-mcgrew]

ive got the shaky steering with my 2 litre brakes too, they havent always been like that either, they used to be sound on another nova. im wondering if its something else on the 'rolling' side or there not bled properly or something.

my car does do this wierd kind of on and off lunge when rolling really slow or braking from slow to a stop, its almost like perpetual motion, but on and off and has a sort of cam/egg shaped feel to it. very strange.

[Stuart]

oh thats ghey, I replied earlier lol

my 2pots on the vx slide back in really easily, prehaps is a design thing for that kind of caliper?!

[Dar]

Is the vibration faster at higher speed?
Anyway sounds like warped discs to me. Or the disc isn't on flush to the hub. Maybe a bit of debris behind one or both of the discs. So you could take both discs off and clean up the mating surfaces with some scotch brite to make sure they are nice and clean. Put a thin layer of copperslip on the mating surfaces as well.

[Graeme]

Disks also imo

[fearless]

Have you check the run out on the discs (when fitted to the car) with a dial gauge ? Although the discs have been skimmed (so we can assume they are ok) - if there is a problem with the bells/mounting method - the overall result will be the same - Vibration under braking

Other possible cause's can be wheel bearings !!!!


Dave

[Lee H]

Not checked the run out.

The hubs and bearings were changed for new about 500 miles ago when I went to equal length big block shafts.

Ran fine for the 500 miles with the Cav turbo setup on previously so seems to be disk/caliper related.

[novaxe235]

I'd put money on it being the disc's i skimmed my rears off my golf awhile ago and they pulsed and vibed after. put some new ones on in the end and its perfect now.

[fennah]

yeah sound like warped discs to me too , but also clean up the hub face with a wire brush and the inside of the disc were it mates to hub , any rust / dirt will cause a judder