I am struggling with my LS2 into a 64 Corvette. I have a right hand drive 53-6430 steering rack and the stock as supplied with my crate LS2 pump. The first time I ran it, all the power steering fluid pumped out of the rack at the pinion input shaft. I have to assume I have blown the seal now, but how do I reduce the pump pressure so that the rack will live and function? I have spoken to Detroit Speed, but they don't even recognise the pump. Lots of people put LS2 motors in other cars. It just cannot be that difficult. Yet I am not able to find the answer anywhere.

 

The pump output "mismatch" is not near enough to blow seals on startup. I'd be looking at the possibility that your lines are swapped. I had a mismatch with my swap, on startup (with the wheels off the ground) the steering wheel started jerking violently from lock to lock, but no blown seals. After installing a reducer, everything was fine. Check with Speedway, they have several different styles of the reducer. You will prolly need to know the exact size and/or make and model of the pump though...

 

I got the violent jerking the first time I started it. I have tried swapping the lines, but I have to find a seal for the rack to stop it leaking. I actually don't know which of the holes into the rack is the high pressure line. It has M16 and M18 threaded inputs. Which is which?

 

Try contacting turnone-steering.com That is their specialty. Maybe they can help with your question. I know of some folks using their C5 Vette pumps and are very satisfied.

 

Here's a pic of mine taken by leaning over the fender. The cloth braided line (top, rear) is the return and the SS braid (bottom, forward) is the pressure feed. Keep in mind, this a LH drive...

 

How did you get those blue thread adapters to seal into the rack? I have the same type of connectors, but because normally you need an o ring, and they don't have one, I used a copper washer. I have not driven the car yet, so I don't know if they will work.

 

It's been awhile... Seems like the LP port had a nylon washer and the HP port had either a copper washer or a rubber o-ring inside it (like a Saginaw fitting).

 

I have spoken to a couple of companies that sell pressure reducers. Unfortunately the Toyoda pump that I have seems to be the one no one currently has a reducer for. And if they can't sell you something, then generally they don't want to help you. So I have taken the reducer out of my pump for a look. I am trying to work out what I have to do to modify this unit to get what I need. I feel there are 2 issues. High pressure, and high flow. To reduce the flow, I think I need to restrict the orifice. Just like re jetting a carburettor. But to reduce the pressure, do I cut the spring and make it shorter? Is the higher spring pressure forcing more pressure down the line? I have read hints of people doing that, but nothing definitive.

 

There was a post here several months back with a link to an article on a 4x4 site (pirate something?) that covered modding these fittings in general. You might try searching back 6 months on that and/or reducer or restrictor...

 

Well, I have had some success at last. I found a supplier in the UK that could match my seal. I made a reinforcement plate to put on top of it to give it some extra support. Having tried to speak to a couple of US based steering specialists, I was not getting a lot of information out of them. The UK supplier said that if I just reduced the hole in the restrictor, the pressure would still build up in the rack under certain circumstances and likely blow my seal again. So I decided to take the plunge and modify my pump. I only modified the restrictor, spring and piston. I made a plug to reduce the restrictor hole from 3.5mm to 2.5mm. This effectively cuts the cross sectional area in half. Then I cut about one and a half coils off of the spring and flattened the end of the spring so it would sit right in the hole. I also ground two little grooves on the outside diameter of the piston. I would have drilled a hole in it, but it is hardened. This is probably the most controversial bit, but I felt that I needed to let some of the pressure bleed back into the pump at all engine speeds.
I put everything back together and fired it up, added fluid and so far no leaks. The steering is lumpy at idle, but seems to be fine as soon as I raise the rpm a little. I have only manoeuvred around driveway so far as the car isn't street legal yet, but it does seem to be working. If it was not so difficult to disassemble the pump (getting the pulley off is hard) I would have done it in smaller stages, but for now I am satisfied that I can get the car in for it's MOT.
As soon as I had finished, I got an email from turn one telling me to reduce the restrictor by the same amount as I did, but don't cut the spring. This was in response to questions I had asked them, but they gave me no further explanation. So Worst case is I have to drive the car initially with lumpy steering at idle until I have the rest of it sorted and can decide then if I need to readdress the steering.

 

Pirate 4x4 is the forum.
But for the most part, a lot of people bitch about slow seepage/weeping of PS fluid coming off the high pressue rack fitting when using an AN conversion. The only way I've seen this to be avoided is the welding on of an AN bung like some dude in Spain did (Nino something).
As for people running these AN conversions, do you find an extra bit of sloppiness in the steering since you're losing a lot of restriction by running a larger-than-OEM line? I've not actually done this conversion yet, but will be within a few months and this is a huge concern of mine.

 

I have never driven the car, so I don't have anything to compare it with. This is a custom build and I am trying to sort out the teething problems so I can get an MOT test (government annual safety test).

 

Hmmm, no leaks here. Guess I'm the lucky one!