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Here is my version of the C303 Corvette power steering conversion. I have mixed feelings about it right this moment but it does the job well.

Why the mixed feelings if it is working well?
Jim

Well, I don’t like how the valve intrudes over the leaf spring slightly. And I’m not thrilled about the smaller tie rod end. But I flexed the truck and it clears fine in that configuration. And the ram takes all the stress off the drag link so... Time will tell I guess. I do like the fact that the valve is readily available from most parts houses.

I think I would have liked the Garrison valve better but they are more expensive and hard to source.

Do you have a link on how to do this conversion?

Thanks

Garry

Sorry, no. I’m aware of two other people on the terrangbil.net site that have done this conversion but not much in the way of a real write up. It’s a pretty simple setup though. There are also several people that have done the Mercedes GW conversion but I really don’t like that method for several significant reasons.

Ok thanks - I will look for other alternatives then.

Cheers

Garry

Garry, what vehicle are you looking at converting? I would say this conversion is easier that the electric setups and most of the other options. But again I’m not sure what vehicle you are thinking about converting because like me you have lots of different odd trucks.

I am looking at the Landrover 101 - has a similar steering layout as the Volvo. From your pics it looks as if you have some sort of ram unit with the original steering box still in place. Current power steering options for my vehicle normally removes the steering box and column and replacing it with a couple of options and possibly cutting into the chassis which I do not want to do.

This setup mostly preserves the stock steering. It’s probably an ideal situation for you. There is an alternative alive to the corvette which I would suggest you look at though. It’s a Garrison type valve and I wish I had gone that direction. It was found on old for pickups and such. You can buy them new but they are costly. Biggest be if it is they fit within the confines of your drag link where the corvette protrudes out a bit.

I’m happy to help any way I can. Feel free to private message me if you are serious about moving forward.

Thanks - much appreciated - the Corvette is a rare car here but their are aftermarket parts suppliers for the cars that are here so I might have a chat to them about their steering assist. Our home grown cars of the late 60s had a ram style power steering but they are considered not good enough with a lot of lag.

Where are you located? All the parts I used are brand new bought online. Aside from som small hardware and power steering fluid it’s all order and fit yourself. Now I did have access to a lathe that made things fast and easy and cheaper of course.

I am in Australia.

Gotcha, I have shipped a fair bit between the states and Australia. I would think you could get all the parts from a US retailer and have them shipped to you.

Parts Geek sells the valve
And PSC direct or Poly Performance for the rest of the parts I assume you can use a standard rover PS pump for the V8. That will be a god send if so.

Thanks but I do not know what exactly is needed - that is why I was hoping there might have been a "how to" link somewhere.

Cheers

garry

Ok, so my situation is slightly unique due to the Cummins engine. But with the parts listed below you should be able to figure out the rest. Please forgive typos etc. as I’m doing this quickly

Here is a quick run down of what to do. Follow the instructions that come with the hoses etc.

1. Measure travel distance side to side of your track bar and purchase a 1.3”-1.5” cylinder with hoses and brackets to match the tie rod travel closest. Go longer rather than shorter.
2. Measure the drag link from center of joint to joint.
3. Draw up valve draglink adapter to be machined The threads for the corvette valve are 1 1/16” - 18 TPI, then up size the rod to 1.3” - 1.4” or so then back down to the inner diameter of your drag link when cut. You should use 2” of material to slip into the drag link tubing. Make the 1.4” section long enough to approximate the original length of your drag link.
4. Cut off pitman arm side of drag link and weld in the above machined adapter. You should use two large rosette welds and then butt weld the end. Hopefully this make since.
5. Create an adapter to fit the 7 degree taper of the corvette valve to the pitman arm you have. This should be a fairly well made steel part in my view. Hand filing is fine. 7 degree or 1.5” taper reamers are fairly readily available for the corvette side. The outside will require machining or grinding/filing by hand. A typical ½” by 1” steel spacer from the hardware store will make a good starting point for this part.
6. Install the Corvette valve with your new taper adapter and secure to the adapted draglink.
7. Center your tires on the truck, then set the hydro ram to half of its travel. Find a location that clears the ram and allows one end to be welded to the axel and the other to the tie rod. Test fit this and cycle the steering a couple of times to make sure there are no conflicts.
8. Weld the Hydro rams tabs onto axle and tie rod once comfortable with placement.
9. Locate a place for the power steering fluid reservoir, this is best if its within a foot or so of the pump
10. Keep in mind the return hose fitting on the pump and the reservoir need to point generally at each other or allow plenty of hose to loop around. The hose in the below parts is 5/8” ID and is maybe 2ft long.
11. Install the fitting in the corvette valve and temporarily install all PSC fittings.
12. Mock up the hose runs taking in account the axle travel and steering components travel. Large loops are desirable here to keep things free.
13. Once hoses are mocked up you can build your hoses and install. The pressure lines to the ram can be swapped back and forth fairly easily. But in the case of the volve you will find the lower port will have pressure when steering left and should be placed on the passenger side of the steering ram. The upper line will of course steer right and be fitted to the driver side of the ram. If you put your ram on the back side of the axle this will be reversed at either the ram or the valve.
14. Now you can fill the system with about 1.25qt of decent power steering fluid. Any decent brand will do, but stay away from ATF due to its flammability in my opinion.
15. Cycle the steering back and forth without the engine running to get most of the air out, you will not be able to get all 1.25qt in without doing this.
16. Check the reservoir level and top off at this point if needed.
17. Now start the engine and feel your nice new steering in action.
18. The steering will be much lighter when driving of course.


Corvette Valve: https://www.partsgeek.com/gbproducts/DC ... kIQAvD_BwE

Reservoir, Pick non Hydro Boost and -6 Fittings with 3/8” hose and 5/8” main return hose or what fits your pump: https://www.pscmotorsports.com/motorspo ... 146or.html

Cylinder 8” But Really 5” would be better on Volvo: https://www.pscmotorsports.com/8-travel ... e-kit.html

Feed hose: https://www.pscmotorsports.com/psc-hk2050.html

1 pcs Return Fitting for Valve: https://www.summitracing.com/parts/edd-39135

3 pcs Valve to Pressure Lines: https://www.summitracing.com/parts/ear-ss991962erl

Cummins Pump Banjo For Pressure Line: https://www.summitracing.com/parts/vpe-11525

Reamer if needed: https://www.summitracing.com/parts/aaf-all11170