PAS Pump Pressure - How do I lower it for a different rack?

[GTMSpyder]

I'm fitting an Audi S4 B5 twin turbo V6 to a Lotus Esprit chassis but the PAS pump on the Audi engine runs at about 1400psi compared with 1000psi that the Lotus (Saab) rack needs. Does anyone know how to reduce the pump pressure so it is safe with the Esprit rack? Is there a relief valve which I can fit a weaker spring to?

Edited by GTMSpyder on Monday 3rd March 22:23

[stevieturbo]

I dont think any bits of the pumps are user accessible ??

Even if the pump can create the pressure......wont the rack govern the pressure ? as ultimately, its the pressure regulator ?

Ive used various combos of pump and rack before. Maybe I was lucky, but they all felt the same, and I never had any problems ( Old Ford rack, Rover pump, Sierra rack, Ford pump, and now Sierra rack, with GM/Holden pump )

[GavinPearson]

Realistically what you want to do is going to be way too difficult in comparison to fitting the old pump to the new engine. Sorry.

[Ffirg 005]

Find a compatible electric PAS pump?

[annodomini2]

GTMSpyder said:

I'm fitting an Audi S4 B5 twin turbo V6 to a Lotus Esprit chassis but the PAS pump on the Audi engine runs at about 1400psi compared with 1000psi that the Lotus (Saab) rack needs. Does anyone know how to reduce the pump pressure so it is safe with the Esprit rack? Is there a relief valve which I can fit a weaker spring to?

Edited by GTMSpyder on Monday 3rd March 22:23

The main pressure regulator will be in the pump. It may be adjustable, but unlikey and you will need special equipment to adjust it.

If you get it wrong and the pump blows there are 2 major problems, 1 it'll probably blow a hole in your engine, 2. if you're nearby hydraulic oil is extremely toxic (especially when it gets under the skin)

Look up 'jaws of life hose failure', ok their 400bar, not 100, but still scary stuff.

GavinPearson said:

Realistically what you want to do is going to be way too difficult in comparison to fitting the old pump to the new engine. Sorry.

This is probably the easiest solution, ok you may need a new pulley and mounting bracket, but it will be quicker, easier and probably cheaper than trying to adjust the audi pump.

Also the audi pump may have different hose fittings so you may need custom hoses.