I know this is an old post, but for anyone still having trouble, there are various flow control valves available, in a variety of flow rates.
From Turn One Steering for example, or others.
https://turnonesteering.com/product/...ow-restrictor/

 

I know this is an old thread, but maybe it is pertinent to my issue. I purchased a 1979 L82 four-speed and have been going through a few systems to get it on the road. The power steering had leaks all over the place so I decided to go through the system. I replaced the seals in the servo valve and the end seals in the hydraulic cylinder. Put in all new hoses and a new power steering pump. I took it out for a test drive and within about 15 minutes it ruptured one of the power steering hoses- the high pressure outlet of the pump just after the steel fitting- and sprayed fluid all over creating a nice white cloud of smoke. I happened to be a few cars back inline at a stop sign with no place to pull over, so I flipped a U and drove it a short distance to where I could pull over. Figured out quickly by sound (pump started to make noise) and feel it was power steering issue. I removed the power steering pump belt- new pump was almost froze up- very hard to turn and the plastic fluid level dipstick was partially melted showing that this got really hot. I drove it home without power steering. Just as a side note, after getting even just a little bit of movement, the steering actually feels better without any assist in my opinion.
When it was working before it blew, it almost felt like TOO much assist, but I'm wondering if that's just how they feel. Questions are: I'm wondering if I have a faulty hose? Or is the system pressure too high? (how would I know- no real way to test. figured a new pump- reman from O'reilly's would be okay) Or would there be something else downstream like servo valve that could cause a high pressure issue? Again, the system worked fine until it blew the line. Servo valve adjusted great and other than lots of power assist, seemed like all was functioning okay. Any insights would be appreciated!

 

Sounds almost like too much heat, or just a bad hose.

FYI There are two control valve springs, the stiffer original one, and the later aftermarket one that makes the wheel feel too light.
And there are at least two flow control valves, the smaller C3 one, and the one the rest of the chevy world uses, which is what the reman pumps have, with too much flow, and also makes the wheel feel too light. Get both and you have a double whammy on too light.

You just need a lower flow pump outlet valve.
Jim is the expert here. He actually designed and/or built these. He had a flow recommendation above. IIRC he said 2.8 or 2.9 gpm?
Many other chevies have a 3.5.

 

Thank you for the feedback! The control valve spring you mentioned- are you referring to one in the power steering pump behind the pressure control valve? Or are you talking about a spring in the steering servo valve? Do you think it would be wise to get my replacement pump from one of the Corvette suppliers to be sure I have the correct setup vs. one from O'Reilleys I'm guessing?
Thanks again for the help!

 

The flow control valve I mentioned is in the back of the pump. It is just an orifice. Corvettes like low flow ones.

The spring is in the PS control valve unit. Original ones were fairly stiff. A lot of the replacements are softer. That ball stud actually moves a little bit against the spring.

Both things drastically affect steering effort. So does caster. Push it as high as you can. Stock is 1-2*. Go for 4 or even 5* if possible.

The commonly replaced high psi spring in the pump does zero for steering feel. But corvettes have low 800 psi ones so they don't pop all those PS hoses. Many reman pumps have 1200 psi ones.

If you can get the steering effort up to 3.5 - 4.0 # measured at the steering wheel rim, it should feel pretty good. That is about what they were new.
(During Low speed circles in a parking lot.)

 

I recently purchased a new Lares power steering pump and double checked that the power steering pump for other Chevy cars was a different part number.

Part Number: 12517
Description: NEW POWER STEERING PUMP
Note: Pump With Reservoir; Includes Filler Cap

I got mine from Summit Racing, I've not put it in yet still putting the rest of the steering parts in.

JT

 

I have a 1980 and just replaced the power steering hoses, nothing else on the steering system. The old hoses were in rough shape...
The steering was unremarkable before and all of a sudden it is TIGHT (manual steering feel). I am at a loss, double checked install, no leaks, no noises. The pump, actuator, and cylinder are all original but wanted to post before I go replacing everything...flushed system and put in new Lucas fluid. Have driven multiple times and cranked side to side while jacked in the front to remove any air bubbles.

Reading above at previous posts discussion around flow rate - maybe new hoses are more restrictive? Doubt it but searching for answers - thanks for any thoughts / feedback!

 

I can't believe new PS hoses are bad / restrictive. But weird stuff happens with repo parts.
I would be more inclined to think when you opened up the system, air got in, and it is not all gone yet.
But the ir should flush out.
Especially if you cycle R to L a few times. Easier while jacked up.
The system should pump near 3 GPM. Even at idle.
You could pull the cap off the pump and make sure it looks like there is good flow inside, at idle.