Electric steering pump in a V8
- Thread starter PeterZRH
- Start date
That was effectively my question. I do know the Saxo pump is 4.5kg. which means the setup is lighter.
sdibbers
Well-Known Member
And no direct engine load either.
Exactly. Electric pumps became a thing for two reasons - packaging (you can stick em wherever there is space rather than build a bracket at the front of an engine - this made it easy for small cars where PAS was still an optional extra) and efficiency. A popular mod these days is to use the all-electric column (no pump) from a Corsa which is better still efficiency-wise and is easily adapted to many cars - I wonder whether that's an option in the P6. It'll mean adapting the shin bin though.
However the reasons I want PAS are slightly different. I actually don't physically have a problem with the manual set-up. At least for now.
Firstly I have three steering boxes, 2 manual one PAS. ALL OF THE BUGGERS LEAK. So one needs to go for rebuilding anyway. I figure by the time I courier it I may as well bite the bullet.
I've found people are not very patient when it comes to non-PAS manoeuvring speeds.
But the main one is I simply want faster steering and as far as I know the PAS box is the only option. To me it's the main thing after the roll bar upgrade that makes it feel ponderous and a bit "old" through the bends. All that wheel turning. Obviously the Corsa electric column or any variation on the ezee-steer assisted steering doesn't give you this. It's great these things exist because old car are otherwise inaccessible to some but they will not match a dedicated system.
Anyway. It looks like I might be a pioneer for this setup in a V8. I already have a 75 amp alternator which should help. I immediately noticed how much better this was with the electric fan - no more dim headlights. The 11AC is really very weedy, in terms of output it's not much better than the dynamo - but better low engine speed output of course. Of the "low cost" upgrades, it ranks as #3 after the roll-bar and electronic ignition. (It was £55!)
For reference, the V8 box is 4.5 turns, the 4 cylinder is 4.25 turns (so the manual steering boxes are NOT THE SAME) and the PAS is 3.5 turns. A typical modern car is 2.5-3 turns lock to lock. The SD1 for reference was an oddly sporty 2.7 in PAS form.
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mikecoombs
Well-Known Member
I got up to doing the actual work on my car then I needed to do the rust first...so it's on hold. It's already PS. I found three possible locations; one behind the left hand headlights in the guard cutout, the second is where the PS pump goes, next to place no.1 and the third is up where the PS fluid tank is. Place 3 is close to the exhaust whereas the other two get airflow (and wet) from the front of the car. On my car place 1 is already occupied by the washer tank and CDI ignition unit so I've settled for where the current pump is but mounted by rubber to the body with electrical connections facing rearward and using the original tank.
Note that in the standard setup the tank to pump line goes around three sides of the engine bay for cooling the oil. You might want an oil cooler in circuit.
Also the lines transmit quite bit of noise to the body so you will need vibration (rubber) mounts for hard plumbing and I'd suggest at least about twelve inches of large diameter flexible hose in the HP line to the steering box to muffle the flow noise. You also need to make allowance for a pressure guage as per manual for testing box and pump.
The two pumps I found when searching were the Saxo one and the GM (vauxhall?) Astra pump. Saxos aren't sold down here so I bought a Holden Astra one online from a wrecker. There are quite a few articles about fitment and wiring etc on the net.
Be aware that the all electric option has been done as you mention but the actual steering column inside the car is of very hard steel and doesn't like being cut, machined or welded. Dismantling the Series two setup inside the car is also a real PITA due to the ignition lock. One advantage with it though is if the power mechanism fails you will still have decent steering whereas in the hydraulic setup it becomes very very heavy with no power.
M
PS. The ps and manual steering boxes are both variable ratio however the variation is opposite. That is; one is higher ratio in the middle while the other is lower ratio in the middle. This is done so that small movements in the PS box at centre don't cause the car to turn continuosly (twitch) when driving straight like GM cars used to do...
Note that in the standard setup the tank to pump line goes around three sides of the engine bay for cooling the oil. You might want an oil cooler in circuit.
Also the lines transmit quite bit of noise to the body so you will need vibration (rubber) mounts for hard plumbing and I'd suggest at least about twelve inches of large diameter flexible hose in the HP line to the steering box to muffle the flow noise. You also need to make allowance for a pressure guage as per manual for testing box and pump.
The two pumps I found when searching were the Saxo one and the GM (vauxhall?) Astra pump. Saxos aren't sold down here so I bought a Holden Astra one online from a wrecker. There are quite a few articles about fitment and wiring etc on the net.
Be aware that the all electric option has been done as you mention but the actual steering column inside the car is of very hard steel and doesn't like being cut, machined or welded. Dismantling the Series two setup inside the car is also a real PITA due to the ignition lock. One advantage with it though is if the power mechanism fails you will still have decent steering whereas in the hydraulic setup it becomes very very heavy with no power.
M
PS. The ps and manual steering boxes are both variable ratio however the variation is opposite. That is; one is higher ratio in the middle while the other is lower ratio in the middle. This is done so that small movements in the PS box at centre don't cause the car to turn continuosly (twitch) when driving straight like GM cars used to do...
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Hi Mike, good to know someone else is thinking along the same lines.
I was going to put it in position 3. If the standard reservoir is here, is heat build-up such an issue? I was planning on adding a cooler in the return loop on the front valence. One of the reasons electric pumps work well is the steering load is very "peaky" as in most of the time it ain't doing much so occasional high currents and stressing the pump for short bursts is not some much of an issue. I'm assuming the original setup relies on this and a largish reservoir to control the heat (as well as the longer lines).
What fluid were you going to use? TQF or the generic fluid for modern steering pumps?
This mercedes c class one looks a good candidate.
I was going to put it in position 3. If the standard reservoir is here, is heat build-up such an issue? I was planning on adding a cooler in the return loop on the front valence. One of the reasons electric pumps work well is the steering load is very "peaky" as in most of the time it ain't doing much so occasional high currents and stressing the pump for short bursts is not some much of an issue. I'm assuming the original setup relies on this and a largish reservoir to control the heat (as well as the longer lines).
What fluid were you going to use? TQF or the generic fluid for modern steering pumps?
This mercedes c class one looks a good candidate.
Just bought this pump. This is how you want to buy second hand parts, with the original brackets, electrical and hydraulic connectors in place for reference. I might be able to re-use the electrical connector. How many have been caught out by finding these were either unobtanium or ridiculously expensive OEM parts otherwise (like more expensive than the part itself)?
This is why I implore people when they strip a car to keep wiring harnesses!
This is why I implore people when they strip a car to keep wiring harnesses!
I would think the "Corsa Column" route might be the more logical route for your application and a car which is highly modified anyway?
That's such a shame. A permanent retreat or a tactical withdrawal from P6 ownership?
I will certainly write it up. I did that for the simpler electric fan conversion (the proper way with a 2 speed non-noisy fan) and the alternator upgrade (done the safe way and not cutting a single original cable). I have a very cheap high power ignition solution in the pipeline too using the GM ignition module which allow us to run 0.3ohm E-core coils rather than the simple points replacement. I love improving the car to be used - I've driven 3000km trips in it and comfort and reliability are important to me. I'm simply not hard-core enough to build such a fantastic beast as you had, that's proper engineering. To me the golden rule is these always need to be executed to at least as good as original or preferably better with the benefit of technology or simply better options, this is a car built to a price 50 years ago, so there's lots of scope. Hence installing the original hydraulic pump seems unnecessary and indeed more complex. Rather like restoring a car and putting back the original "period" rustproofing!
cobraboy
Well-Known Member
Tactical - thinned the fleet.
Will always have this though
3.9 Rover, LT77, SD1 front calipers, MG (Rover) front crossmember, MG (Rover) rear axle - A Rover special
Are they the Police spec 4 pot calipers? If not that's a good upgrade with the matching vented discs.
cobraboy
Well-Known Member
H
They are the large 2 pot from IIRC a 2600. I looked at the 4 pot, they wont fit behind the wheel, and besides they weigh a bloody ton.
When I first fitted the larger fronts the rear was still on drums, the front was massively over braked, rear discs balanced it up.
You are spot on regarding cooling, the discs are solid, they need air to them, otherwise on a track they boil the fluid.
I worked out pad and piston areas on the SD1 twin pot versus the Princess 4 pot, the SD1 are equivalent for absolute peanuts money, so that's what I fitted, the pad is the same as an MGBV8 so there are plenty of compounds available.
Apologies for the detour !
They are the large 2 pot from IIRC a 2600. I looked at the 4 pot, they wont fit behind the wheel, and besides they weigh a bloody ton.
When I first fitted the larger fronts the rear was still on drums, the front was massively over braked, rear discs balanced it up.
You are spot on regarding cooling, the discs are solid, they need air to them, otherwise on a track they boil the fluid.
I worked out pad and piston areas on the SD1 twin pot versus the Princess 4 pot, the SD1 are equivalent for absolute peanuts money, so that's what I fitted, the pad is the same as an MGBV8 so there are plenty of compounds available.
Apologies for the detour !
clive P62
Active Member
Snap same one as I've got on my saxo
mikecoombs
Well-Known Member
The Horizontal layout is a good idea for P6. My Astra unit is vertical and it makes it rather tall if you need to keep the tank on top. Shame there are no Saxos over here in the antipodies...
I'm thinking of including a small pressure tank (probably from a brake system) to ensure there is a bit of steering should the power go off...
I'm thinking of including a small pressure tank (probably from a brake system) to ensure there is a bit of steering should the power go off...