412 Spares sources

[geo]

Originally Posted by peterg

For my 403 which were described as 406/407 upgrade. The piston cylinder
was described as 2 1/8" by Power Track Ltd.
. . .
My understanding is that there were only two types of Dunlop brake and both
were serviced in the same way, so you can probably rely on the advice of a
vintage Jaguar engineer.

Sorry, I have not got my old Bristol info up here on the island, but I do remember from 30 years ago when I redid the cylinders and plumbing of my 408 (Mk. I) that the Jaguar and Aston Martin/Lagonda Dunlop bolt-on cylinders all fitted in terms of the bolt holes, but the diameter of the cylinders themselves did vary by between 1/8" and 1/16".

Sorry, I cannot remember which ones were identical with the ones used by Bristol, but I do recall a well-known Jaguar restorer claiming that as long as the cylinders were matched on the same axle, he did not fuss too much if he could not get exactly the same size. He also claimed that Dunlop played round with different sizes for the same models during the middle 1960s as it was still a developing technology.

The least said about the handbrake the better, but I was surprised just how good the Dunlop hydraulic system was when completely overhauled (I only renewed the seals in the master cylinder).

George