About 1 year ago, I changed the steering box to a close ratio box. Don't recall the vendor but probably OPGI.
Anyway, since I put the box in, it seems a little squirrelly when driving down the highway in a straight line and when turning, the steering wheel does not return to center after the turn like it used to do. This happens when turning in either direction.
Anyone else experienced something similar that can help?
Thanks

 

More details would help - ratio? 12:1, 12.7:1? Those are the typical A-body choices - i.e. 2.75 turns L to L vs. 3.25 L to L I believe would generally be the difference between them.

By 'squirrely' do you mean the wheels respond quickly/notably to any steering input/movement as you drive? I think that could simply be a by-product of the fast-ratio setup, most noticeably if you have the tighter-turn radius box (2.75 turns).

your alignment could need tweaking as well to address the return-to-center issue, and maybe that would also help alleviate the at-speed stability issue.

I'm sure others more knowledgeable in steering system tech will add their thoughts.

 

Well, I went from 4.5 turns lock to lock to about 2.8
FYI, the car drove fine before just a lot of play at center position that would not adjust out with the old box. The rest of the front suspension is all new.
I feel like I am always fighting it a bit in a straight line. Not so much because of responsiveness but kind of a stiff feeling
I had the alignment done and this made no difference.
I drive several cars with quicker steering like Alfa, Jaguar and Porsche so I am used to quick steering
Hope this info helps

Thanks

 

Keenly following along since I'm soon going to change mine soon ('71 CS convertible).

 

The box may be set up a little too tight. The nut and allen screw on top of the box adjust how much play there will be between the steering shaft and pitman arm shaft. Too loose and you will have excesive play in the steering wheel, too tight and the box will not return to center. Try backing that screw out a little. To adjust, put an allen wrench in the screw and loosen the nut with a 9/16 wrench. Make small adjustments (1/4 - 1/2 turn at a time) and then test drive the car to see how it feels. Be sure to tighten the locking nut again after adjusting. I have a fast ratio box on my vista and these boxes do tend to be more responsive giving the "fighting" feeling you describe. You may need to compromise between steering wheel play and acceptable return to center feeling. Just play with it until you are happy. Something to remember, your Alfa, Jag, and Porsche have fast ratio racks. The Cutlass fast ratio box is an improvement over the factory box, but it will never be quite as good as a true rack and pinion due to all of the moving components in the rest of the steering linkage.

 

My apologies
I guess I should have given more details. I already tried adjusting by backing off on the screw a little at a time. While it made it better, it did not really make that much difference and I was starting to get a little play in the box from going too far.
I was starting to wonder if my stock pump was not strong enough to handle the power needed for the close ratio box. Possible?
FYI, the Alfas I work on are old spiders with a similar gearbox to the GM cars and they are very responsive almost like having rack and pinion. Not sure how they did it and have wondered for years.
I guess what i am/was hoping to achieve is to have decent response without a bunch of play. That is why I rebuilt the entire front end previously.
Maybe I should have gone back with a stock ratio box??
I am working on a 1980 Avanti right now and it also has a recirculating ball steering box plus a power valve and piston like the old Corvettes and the steering in that car while not quick is tight and responsive. Similar to what I envision a good steering Cutlass would be like.

Any more ideas and suggestions? I appreciate the quick responses

 

You may want to go to a rebuilt stock ratio box. I have the fast ratio box with all new front suspension in my vista. I have it adjusted for decent return to center feel without much play, but it does have some of the "fighting" that you describe while going straight but, that is also partly due to the wide low-profile tires on the front that like to follow grooves in the road. My cutlass hardtop has a rebuilt stock power steering box (also all new suspension components) and that does not have the "fighting", just tight with little steering wheel effort. I will say that my Toro probably steers nicer than both and other than the lower ball joints, all of the front suspension components on it are still original (83,000 miles).

 

When I purchased a Lee fast ratio box, they supplied a modified PS pump, best modification I’ve done…

 

Be sure your alignment - ESPECIALLY caster - is set properly. Return to center is governed as much by caster angle than anything else. Newer quick-ratio boxes are designed for newer cars with higher caster angles. 60s and early 70s cars have about zero caster to make steering effort easier.

 

What Joe said............ My 83 Delta with the LS3 has QA 1 control arms. The alignment specs are 4 to 7°Caster. I am using a mid 80's 442 quick ratio box. The car drives great

 

Like Joe said, it's most likely the alignment. What are the alignment specs? Is the front suspension stock and set to stock numbers? If so, then this is just the nature of the beast. You can use a stock box that is pretty sloppy, or use a close ratio and/or lower assist box, but it won't behave very nicely with the stock alignment. Pick your poison. You can think of it like the stock box soaks up the mess of the stock suspension, while a modified box amplifies it.
Also, are you running stock tires up front or something wider? Wider tires will also amplify any issues in the suspension design.

The pump has little, if anything, to do with return to center and "twitchiness".

 

Actually what Joe said was DON'T set it to stock numbers, increase the caster angle.

 

Okay, I am running a totally stock suspension set to stock alignment specs. Tires are radials mounted on stock rims and not that wide. Don't recall the actual size.
So are you saying that more caster will make it steer better?

 

What exactly is a "close-ratio" box? Is it a variable ratio with less difference between the ratios?

 

I wondered the same, and assumed it was a "quick" ratio? IDK

 

Yes, that's why I said it twice in this thread. Increased caster angle increases the "self-centering" force that brings the wheel back to center. This is one of the biggest differences in steering feel from older cars to newer ones. When manual steering was still an option, automakers kept caster angle near zero to lower steering force. Unfortunately your suspension won't have enough adjustment to let you get to 4-7 deg without aftermarket upper control arms, but crank in as much as you can. Even 2 degrees will make an improvement. And be prepared for the alignment shop to push back on settings other than stock. This is why I do my own alignments.

 

My gearbox was leaking and I replaced it with an O'Reilly brand aftermarket stock replacement box. There was slop in the original box, but I didn't realize it until I replaced it. The car drives like it was engineered to do so and I am happy with the result. In my opinion, unless you are ready to upgrade entire systems, the original setup is usually the best, modern tires and shocks are the exception.

 

quick ratio. 2.8 turns lock to lock

 

Well, as soon as i feel up to it. (recovering from a knee replacement) and the weather cooperates, I will adjust the caster and see how it feels.
I think adding a shim to the front of the upper A arm and removing and equal size one from the rear should not affect my camber that much. True?
Unfortunately, the weather has been nice and warm for the last couple of days but my knee said NO!!

Thanks

 

You want to remove from the front and add to the back. That means moving the upper ball joint rearward relative to the lower. The spindle axis needs to intercept the pavement in front of the tire contact patch, not behind it. And yes, swapping equal amounts of shim from front to back will accomplish this with no (or nearly no) change to the camber. This assumes that you have the same thickness shims on both sides. Unfortunately one shim is unlikely to provide much caster change. On my 67 Delta I have no shims at the front, quite a bit at the back, and I can't even get 2 deg. I'll be modifying a second set of upper control arms to relocate the upper ball joint rearward.

Note that the definition of "positive" and "negative" caster angle vary. I've found plenty of completely conflicting references. Suffice to say that the caster angle needs to look like this. Also be aware that the more you change caster, the more it can cause a toe change as well.

 

All spot on, the only thing lacking in this post is which side of the car your diagram refers to.

Think of the caster on the wheel of a small cart for carrying a load or around your house, or on a front bicycle wheel. A castered wheel either leads or follows, depending on the angle of the axis. On a car you want it to lead, as Joe indicated pretty much as large as mechanically possible.

There was a great write up in JWO several years ago about front end caster. Can anyone name it?

 

Thanks.Joe
That is what I meant to achieve. I just forgot how the cutlass is shimmed for a moment.
I really appreciate your advise and patience in this matter.
I will post what happens after I get that done