Anyone had discs turned on the car?

[Geeman]

I have a set of new front discs for my 1984 Turbo that I fitted.  I checked the runout and endfloat on the discs and hub and all good, but I'm still getting a judder under braking.  I've checked the steering and suspension etc and am sure its all OK.  I spoke to Steve at SJ and he said the best thing to do is have the discs turned on the car.    It looks like the caliper has to be unbolted and held out the way for the cutters to access the full faces of the disc.  There are special adaptors for the machine to attach to the hub wheel face.  Looks like the PCD is 5 bolt on a 120mm PCD.

I have actually found someone locally who can do this but before I commit has anyone had this done before?

Was the machine able to fit on the Esprit?

[jonwat]

1 hour ago, Geeman said:

has anyone had this done before?

Can't answer your question but here's a video of it being done on a Boxster

[drdoom]

Let us know how it turns out for you.

[CarBuff]

I had rotors turned on-car on a Honda, once. Worked fine...

 

Before you do that, assure that the hub>rotor mating surface is clean, and that the calipers are not binding (feel the wheel centers after a 10 - 15 mile drive, both sides should be equally warm). If the calipers are binding, replace or rebuild.

[andydclements]

I'd suggest having the surfaces of the hubs machined true first, so that if there is a slight run-out to be dealt with by the on-car machining it's rotor only and so any future change of rotors doesn't re-introduce it.

[Chillidoggy]

What type of calipers are fitted to the car? Are they the sliding type?

[drdoom]

My veteran mechanic for the runabout cars has advised that warped rotors has long been discounted as a source for such vibrations. Instead the common cause is uneven pad material deposit on rotors, yielding the wobble on rotation. Not inclined to suspect the hub faces but a light skim clean up of the rotors appears to be in order.

[Escape]

Indeed, it's far more often deposits and not warping. But the deposits will be taken off when the discs are turned as well, so the end result is the same.

[Andyww]

A judder under braking on early Turbo / S3 can be caused by the anti roll bar to lower link nuts coming loose.

[drdoom]

Well modern replacement parts may no longer be what they once were but over the years I drove an Elan there was never word of warped rotors on Lotus of any series. I drove the piss out of the car on track at times, never blanched at attacking roads when the mood suited and the worst I experienced was fluid boiling when running laps on a circuit with a wicked hairpin at the end of a long downhill straight. Sorted that out with better fluid, the rotors serving flawlessly throughout my 12 years of ownership. FWIW