I replaced the power steering in my '75 with the Borgeson setup -- after driving on a hot day for a few miles, the steering got very stiff.  Contacted Borgeson who sent a replacement steering box.  This time I also had the power steering pump replaced.

This one is doing the same thing.  Borgeson says the problem is not with their steering box.  I've checked the hoses (which were new last year) for kinks.  The interesting thing is that as soon as I turn the key off, the steering is no longer hard to turn a few inches back and forth like it was with the engine running, indicating to me that there must be something in the power steering box making it stiff.

Borgeson says that a rebuilt pump could be the issue (but it was the same with the previous pump on the other steering box) and it worked fine on the old setup.

I asked them if it was possible that they got a batch of steering boxes that weren't machined correctly -- they said no. 

I'm at a loss as what to do.  Here it is prime cruising weather and this issue crops up.

Any ideas?

Works ok until it gets hot? Perhaps it needs a cooler on it, but it could still be an issue with the gearbox. Pump either works or it don't. Only possible pump issue might be the regulator valve hanging, but that is unlike 2 pumps having the same problem.....UNLESS there is a lot of metal in the system.

Refresh my memory.  What was wrong w/ the OEM system?

There was a lot of play in the original system.  I had tried to adjust it to no avail.  And everyone said the Borgeson system provided better steering.

I'm going to try to shield some of the engine heat from the steering box and see if that helps.

One thing I noticed;  when the steering gets tight, there is a squeak coming from the steering column.  I assume it is being transferred up from the steering box, but you would think the rag-joint would dampen that.

The Borgeson power steering is much quicker.  12:1 vs 16:1 and is a more modern design.  Eliminates the hydraulic cylinder and what ever that leaky steering valve is called.

It's just better unless you are an NCRS guy.

Externally it looks like a standard recirculating ball steering unit similar to the one GM uses on their other vehicles.

When I started AutoXing, I switched the linkage to the quick position and installed a pickup truck relief valve. The stock relief valve would limit how fast you can turn the steering wheel when you are making tight turns quickly.

Bill: When it gets hot and the steering gets stiff, you might try disconnecting the rag joint to see if the stiffness is in the steering column itself.

I autocross my LT-1 and the 16:1 box is just too slow.  I am elbows and arse holes in the cockpit turning left and right.

Everyone I know raves about the Borgeson steering and most like it better than the Steeroids rack and pinion.

Seems strange that I'm the only one it seems with this issue.  You guys that race, I would think, would encounter heat-related issues before the rest of us.

I fashioned a heat shield between it and the exhaust, I'll see tomorrow if that helps.

Is the stiffness when it gets hot about the same as if you were driving it with no power steering at all or is it stiffer than that?