Good to know. Thanks for the info +++

Anyone have the part number for LWB D2 handbrake cables?

Does the LWB VW Phaeton have a mechanical e-brake or is it electrical?

What about the very early model year D3 LWB e-brake?

4D0609721N (left) and 4D0609722M (right).

Thanks. Good thing I'm not in a hurry on this and have some time to find them.

Another question. Why are the C5 RS6 discs so expensive as they are not 2 piece rotors so why the high price?

They are 2-piece rotors, just staked together rather than bolted like the RS4.

Weights from memory:

RS4 - 5.5Kg
RS6 - 6.5Kg
A8 - 14Kg!!

Interesting.

Those weights are for the front rotors? Either way that's a huge weight savings between the A8 and RS6 rotors. The B7 RS4 rotors have a very low rotor hat offset vs. the C5 RS6 rotors correct? So the RS6 rotors will be easier to deal with then the B7 RS4 rotors?

Is there a difference between the front B7 RS4 calipers and the front C5 RS6 calipers?

Yes, the B7 rotors are almost flat, whereas the C5 has about 6mm more offset iirc. That's all down to the C5 RS6 having more offset on the hub as it uses D2 wheel hubs (which sit 6mm further out than B5 / C5 A models, so the disc is different to accommodate that. The B7 I suspect uses the same upright geometry but the A wheel hubs.

I haven't had the two calipers side by side to compare. The part numbers are very close, and from pictures they appear to be the same.

The conversion I did involved removing the 90 degree adapter plate which comes stock on the RS calipers, and then fabricating the flat plate to maintain the radial mounting. I suspect it may be possible to retain the adapter and use A8 uprights with axial mounting, although it may need some spacers and / or A wheel hubs. I was to find that out this year until corona messed everything up.

Referring back to earlier comments does the increased mass of the A8 versions improve heat dissipation so reduce brake fade and other issues?

No, bigger mass can absorb more energy so takes more time/longer braking to heat up by the same amount of degrees but it also takes longer to dissipate it as it holds more energy, it may be better for single braking episode but not for several successive occasions like track use. Dissipation is more related to airflow and surface area.

Thanks for all the great info everyone +++

This is my dumb question of the day. I'm guessing the C5 RS6 calipers are made from aluminum?

Yes. All the Brembo multi-piston calipers are aluminium. The D2 S8 and RS versions are split calipers meaning they are two halves bolted together. The Porsche 17z and 18z are monoblocks so a single casting (hence a lot lighter but also more expensive to make).

Many of the Audi sliding calipers are a combination of aluminium and steel. The HP2 on later D2s for example has an aluminium piston housing but steel slider and pad carrier. I think the D3 360s are mostly aluminium too.