PS Rack Question

I forgot to mark the PS Rack when I disconnected the hoses.
Which is the input fitting from pump (high pressure) and the return (low pressure) fitting?


Thanks (I did search first).

No problem, I found this pic on Clarks Garage.
High pressure connection is the lower port.

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First movement of the car under power today, problem, the power steering is vicious, I talked to Turn One about this as I was concerned about the orifice size in the AN adaptor.

From my description of the PS being very sensitive and over controlling they believe that I may have the connections reversed.

Would someone kindly look at their car and identify which connection port (Upper or Lower) on the rack is the high pressure line from the pump. Picture might help.

I thought I had this licked, Many Thanks, Mike

I just put mine (968 daily driver) back together tonight and that is how I did it, the high pressure hose from the pump went on the bottom.

Hey Mike. Same here, pressure inlet is the lower one. The upper one went to the cooler then reservoir. This info is from my notes having taken things apart just a couple weeks ago. Good luck.

Rich

Thanks Guys,

I'm positive that I connected the HP to the bottom and the return to the top ports. Car is at the exhaust shop, will double check it tomorrow. I may have the wrong size orifice in the HP AN hose fitting, Turn One advises that the hole size dictates how the steering behaves.

I may be over reacting as I have been daily driving my 68 MGB GT for a year and half and it's steering requires muscle when manouvering in tight spaces.

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Your car looks great.

Hi Mike,

Ditto on the look! For my Turn One pump I just used -6 AN teflon lined braided SS, I think Russell Perfomance stuff. Mine feels just right, I used 3/8 rubber hydraulic for the return line, through the stock cooler to the reservoir on the pump. So far so good.

Thanks again guys, it certainly been worth all the work.

I obtained my steel AN-6 pump fitting from Turn One, the orifice in the fitting is available in different sizes. Turn One indicate if there is any hesitation in the PS operation then the orifice diameter needs to be enlarged to increase the flow rate. I may have the reverse situation and have to decrease the flow rate.

Any progress on your PS issue? I'm going to use the stock GM pump to begin with and cough up the $$ for the TurnOne pump only if I have to. Do you know if it's the same threading for the adapter to AN-6? Would I be able to use TurnOne's lengthened adapter with this orafice with the stock GM pump? If you figure out which orafice size is correct, please let me know.

And I'll say too, your car looks awesome. Are those TPC's headlight buckets or IFC's? Hope you get it rockin' and rollin' soon.

Rich

The AN fitting in the Turn One pump is metric and steel, not a good idea to use aluminium fittings on the high pressure side, If you read back through the archives you will find that the stock GM pump is not compatible with the Porsche rack. Porsche runs at a higher pressure. Some guys have used Xschops brackets to use Porsche pump in the GM position on the LS1.

I stopped by the exhaust shop today to confirm that I have not reversed the lines to the rack. Guess I am going to have to play with the orifice size when I get the car back.

Yeah, I see both success and failure reported with using the Chevy pump and Porsche rack. For $40 I got a used pump and will try it. I'm hoping the same adapters and lines necessary for the TurnOne pump will work for now with the Chevy pump.

What I'd really like to do is make a bracket to put the Porsche pump in the LS1's a/c location. That'd let me leave the reservoir in the factory location and use all of the stock 944 lines. Where I'm stalled is finding a pulley that'll take a ribbed belt. The late '80 BMWs used serp belts where the earlier cars used v-belts and I read the pulley's are interchangable. Further, those pumps were made by ZF just like the Porsche one. But looking at pictures, the bolt patterns on the pulleys look different.

Porsche 944 pump:
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BMW e34 pump:
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I removed the outlet fitting on the Turn One pump yesterday and enlarged the orifice to 1/8".

There was an improvement in the steering, not so nasty and notchy, still sensitive. I might take it out to 3/16" when I fix the busted oil line to the filter.