[ecm911]

Symptoms:
High speed (over 60 mph) under braking - Front end hoops and wheel vibrates with occasional slight pull to left. The vibration/hop is more pronounced as speed is increased.
Nothing on lower speed braking
Drives straight and no issue with no braking as well.

Car is SC t – dedicated rack car, suspension was replaced 3-4 years ago. Also Have brake cool ducts.
What I have done –
Replaced both front brake calipers with rebuilt ones (when the problem started – right front caliper was stuck).
Replaced right front rotor and wheel bearings including inner hub.
Kept the same brake pads in (Hawk blue). Did a break in procedure.

Just did a two day track event and the problem persists – but it is much less server.
But nonetheless I have to get this resolved.

So I inspected and pulled and pushed everything on the front end with nothing coming to light, other than the front rotors.
A wheel bearing have a very slight movement but seems like an acceptable level. Inspected all brake pads – wear seems even – however the outside pad on the right front appears to have lost some material in the center of the pad –
The right front rotor is warped (pad material I assume), left rotor is fine.

I fear it is still in the right front caliper and would probably go with a brand new one this time. Just want to make sure this is the problem.


Here is my plan of attack –

Replace both front rotors (just to eliminate any issues here).
Check wheel bearings – replace if needed (Both side were recently replaced) make sure they are tight.
Replace with new brake pads – I have a set of ferrodo. – break them in.
Replace front tires with newly balanced ones – need them anyway.
Take a test run and see if I can replicate the problem.
If I can replicate the problem immediately it still could be the caliper but I have a least eliminated the rotors and pads as a problem.

I know that I may not be able to replicate the problem until at the track when it all heats up etc. But at least it is worth a try and if I can replicate it, I keep investigating…

Suggestions or comments well.
Thanks all..
Earl