Diff, Steering and front axle 408

[lansdownplace]

BCL fitted new Spax to the front of my 411 and tightened them right
up almost to max hardness with a mid/soft setting on the rear. It
transformed the handling, you can throw it around quite a lot. You
may have read in the old books that they used to test every
shockabsorber before it was fitted, rejecting loads. I was
astonished to find that they still do this, and using the same
machine which is attached to a tiny 4cly car engine. It produces a
card with a graph on it. They still reject a surprising number of
parts.

Paul

[408Berlin]

Dear all, thanks a lot your answers which are helping a lot - guess I have some work to do. Hans

[Kevin H]

Was the 408 steering box a 'Marles' ?

Brakes were Dunlop, probably very similar, if not identical to Jag E-Type and Aston DB4.

I wonder if you could convert to the larger Girling brakes.

[Nick Challacombe]

According to mt MOT man , a set of Dunlop Discs set up well are far better
than Girling.
My car on his MOT meter pulls up a far greater force than many moderd cars
he tests.
They are indentical to an early E type upon which they did not work as well.
Maybe something to do with the Lockheed master cylider and the large servo.
The 407 and 408 were indeed Marles, hense I think the factory change on mine
to a 409 box.

Nick.

[408Berlin]

If Bristol used Marles steering boxes they should be also built into other car of that period? Do you have an estimate about prices for good steering boxes - maybe as P/X for 407 - to 409 models? Concerning brakes - my 408 is converted to Girling - very good results.

[Kevin H]

Originally Posted by Nick Challacombe

According to mt MOT man , a set of Dunlop Discs set up well are far better than Girling.

I guess that's why Bristol changed to Girling brakes on the 409!

And Aston changed from Girling to Dunlop for the DB4 then back to Girling for the DB5 and DB6 and V8.

I had a DB4 with the exact same Dunlop brakes. They were adequate so long as you didn't have to use them often. When I did the 4 day Adelaide Classic rally in my DB4 I found they started to fade quite badly once they got hot.

The fact is, the Dunlop brakes were two piston calipers with a very small friction pad surface area. Whereas the Girling brakes brakes had three piston calipers and at least double the pad surface area. The Girlings were far superior brakes, which is why they were also used by Aston Martin, Jensen, Iso, Ferrari, Maserati and TVR.

[seanmcs]

We've had this conversation before. I think that Nick makes an
excellent point: setting up any brakes is a big part of it. I found
that on the 406 the Dunlop discs were just splendid. With the
booster, capable to lock up the wheels with one aboard. Even the
drums on my early 405, with Alfins, are pretty good, and Sebastian
has just added a booster, so should be even better now. I suspect
the Dunlops on the 406 Zagato will do more than you ask. We'll know
in earlt=y 2010, hopefully.

Best. Sean

ps: Interesting that 40% of the Bristol Zagato 406 models are on the
market now. Never before

[Nick Challacombe]

Try ACCS or Brian May. details as before.
BCS not likely to have second hand ones, I think they found the Marles box
unsatisfactory which is why they
retro fitted 409 boxes to the 407 and 408 when in for service etc.