Theo the Astra PS pump will work fine, most of the improved production guys run them now because they are cheap and they work. And if it fails then you buy another $180 pump. If they can work for 300,000k in an Astra then they will work in any other car. Mine has worked faultlessly, unlike the factory holden pump that kept boiling the fluid every time I went out.
Race pumps are expensive and still fail.......

Oh come on ash, little hook and big worm and not even a bite.. I need to try harder don't I. :LOL:

I've given this some thought and I think the main problem with power steering pumps and racing is that they are just spinning them too fast. A PS pump will last 100,000+ KM in a road car but it's running at the RPM it was designed for which is pretty similar to the crank RPM so about 1800-4000 RPM. In a race car it's running 7000 RPM + which are speeds they are just not designed to sustain.

Also think about how they operate, the pump makes enough pressure to overcome heavy steering loads at low speeds while parking. At this time the pump is probably only just above idle. That tells me that running at higher speeds means the bypass valve will be constantly shunting all that extra pressure away and generating lots of heat. Just wasted pressure

The answer is to severely under drive the pump. I settled on running a 25% under drive harmonic balancer which was the biggest under drive I could buy off the shelf. I've also machined up a larger PS pump pulley for a bit of extra under drive. Add to that a decent cooler and probably some synthetic fluid and I reckon the PS pump should survive extended abuse.

http://i1247.photobucket.com/albums/...psmddvzv3z.jpg

The advantage of the Electric PS pump is they produce a constant pressure with the pump only really bypassing pressure when there is no load on the steering.

Ash, you seriously need to look at sourcing parts as I got the Astra pump for $44. Had to pull it out of the car myself and what an ordinary job that was! Took your advise and got all the wiring and now the challenge will be to decide where to mount it.

Matt, after talking to all sorts of experts who were scratching their heads with what my rack is (and probably yours as well) is that it is off an LH - LX Torana and not Cortina.

Discussed this with DSC and they are now using Subaru WRX racks and to fit, some suspension mods need to be done so will take the trusty camera down there in a few weeks and take some snaps/get more info and then decide exactly which way I will go

Two cents worth as a design engineer... Id repeat what Mike said.. under drive the PS pump, there is little assistance required at speed, use a synthetic fluid (I had heard one P Brock used a Mobil fork lift trans fluid on a Monaro he raced in Targa) and add a cooler or even a simple cooling loop of exposed / finned alloy tube to increase the volume of fluid in the system all of which will support heat dissipation.

My 2c as an average Joe (not having a go at anyone)....
Yep I agree, in theory, the underdriven balancer (mine is only 12%), a large (heavy) transmission cooler and Prolube AG Trans (hydraulic) fluid should work, and may work in other cars, but didn't work in mine. It would still blow transmission fluid out of the small breather hole in the cap. Mine was only spinning to 6,200rpm so not really high revs. Could be the fact the cooler didn't get much airflow in the engine bay. I did have ducting running to it..

I spoke to a power steering specialist in Brendale (Brisbane) and he said yep the VE commodore etc power steering pumps are not much chop, they all have the same problem if they are sustaining high(er) revs.

Some of the earlier LS1 pumps you can replace with a Saginaw (speedway) pump and they will work all day without a problem but they won't fit on a VE or later car because of the different pulley offset.

He offered me a race electric unit that was about $1,000 but I thought I would try the Astra power steer solution first.

Having said that..... Geoff Taunton runs a VE type power steering pump in his Cobra and his engine (LS3) runs to nearly 8,000rpm and I don't think he had problems with it.... I do think he had a pretty big trans cooler across the front of the car.

The first time I took the car to the 2 days of thunder event up here a lot of the improved production Commodore guys were asking me if I had problems with the power steering..... After that weekend a lot of them changed over to the Astra setup. Next 2 days of thunder a year later...... 90% of the LS engine cars were running the Astra pump lol.

Theo you got a great deal, I even paid $165 for my 'spare' one....

The electric pump certainly makes sense. I looked at the Astra one too. It also means you still have power assist after your engine dies. I imagine suddenly getting heavy steering when your motor shuts down during a race could make it a bit more difficult to bring the car off the track safely. Electric PS pump would mean you would still have full assist.

The VE commodore KYB power steering pumps can be replaced with a Delphi unit, the original KYB pumps don't like revs and are known to fail.

There is also the ELECTRIC power steering units, which bolt onto the steering shaft.. some even have programmable resistance at speed, no fluid, no heat, no leaks.. :)

It has a lot to do with the weight of the car. In my old VX SS the power steering would overfow on the track until I added a cooler. In the Cobra it has more power, I go faster, but have no cooler and have no issues so far.

No improved rack ratio either.

One of the advantages of going to power steering is usually the quicker rack ratio. That was the main reason for me switching to power steer.

For example the VL Commodore manual rack that I had was 4.48 turns lock to lock. The manual rack has a ratio of 23.3 to 1 at the ends of the rack, and a ratio of 19.7 to 1 at the center of the rack.

The power steering rack has 2.68 turns lock to lock and ratio of 11.8 to 1 at the ends of the rack, and a ratio of 17.2 to 1 at the center of the rack.

This all adds up to much quicker steering and not needing to shuffle the wheel back and forth when on the track.

I used a Hydro-electric power steering pump from a 2000 MR2 Spyder and it works perfectly.
It is a fully self contained unit which when you hook into your speedo output is then speed sensitive.
Uses a brushless motor which draws very little current.

My cobra pulley driven pump spins to over 8000rpm and its fine. That said it runs a cooler and runs very good synthetic fluid.

Someone needs to post this topic to Todd and Rick Kelly. They continue to have PS pump failure on their Nissans. Enough so they crashed at their Winton practice this week due to the ongoing PS issue.

PS pump
 

Guys,

I have had PS pump issues I the past, the new original units are rubbish.

I purchased a Ford BA turbo unit with the correct pulley ( forget the brand)

And the 25% reduction pulley and a cooler. It has worked for 5 years but after

Shelbyfest this year it is leaking from the pressed gold coloured fitting.

Tranny fluid and it seems engine oil is leaking, it might be the tranny fluid

Is dark from the black seal. But it needs to be replaced as it's leaking onto the

Alternator and it is starting to get a bit knotchy.


Stiffy

I am a bit lost for the reasoning of power steer on a Cobra.
I have manual steering and it is more than light enough.
I was always told the major gain in power steer was less turns lock to lock (for racing purposes), but if you are fitting an Astra power steer electric unit to a car with a manual rack, you are not going to change the lock to lock turns?

Dave the Astra unit is a hydraulic pump, its just electric and not belt driven.

Ok, I thought the Astra was an electric motor fitted at end of steering column.
I think late Barina is like this, and I just thought they would be the same.

Theo, also make sure your electrical system is up to the task, if memory serves me correctly I think that pump can draw up to 80 amps.....ouch!

That's the reason I went with the late MR2 unit.
It draws bugger all !!