ur quattro Diff lock vacuum pipes routing

[conor2469]

My 83 urq has both diff locks located at the rear. I am swapping to the later setup where the diff lock for the central diff is located on the gearbox. How do Audi route the two vac pipes out for this location, through the bulk head?

[Tim C]

Yes, as you thought.

You can see them right in the centre of this photo, between the pedals.
They come out just below the rack and then loop back round to the actuator.

It's easy to show on a stripped out rally car .

[conor2469]

Thanks Tim that is perfect, I appreciate that

[Gaz]

Originally Posted by Tim C

Yes, as you thought.

You can see them right in the centre of this photo, between the pedals.
They come out just below the rack and then loop back round to the actuator.

It's easy to show on a stripped out rally car .

Sorry to go off topic, but what is the switch/wire on the clutch pedal used for?

I know the one on the brake pedal is for the brake lights, but why is there one on the clutch?

[Val]

Cruise control

[martinws]

Originally Posted by Val

Cruise control

Or launch control if so inclined!

[Tim C]

Originally Posted by Gaz

Sorry to go off topic, but what is the switch/wire on the clutch pedal used for?

I know the one on the brake pedal is for the brake lights, but why is there one on the clutch?

The car runs on an aftermarket ECU (Emerald) which has all sorts of functions.
A couple of which allow you to adjust things for different gears, such as boost pressure.
It works out which gear the car is in from the engine and road speed, once you have programmed the wheel circumference and ratios.
The clutch switch tells the ECU that it has been depressed and to ignore the strange road and engine speeds! It remembers the last gear until the clutch switch is re-made, and then starts working it out again.

The ECU can also use the clutch switch to allow full throttle gear changes. I think it knocks back the timing to reduce power as soon as the clutch is depressed, so you keep the throttle pressed to the metal. But we haven't been brave enough to try that!