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Discussion Starter #1
Can someone tell me what the difference between a 20:1 and a 16:1 ratio will do on a manual steer car with the borgeson box? Also, since this is for a 68 with the collapsable column and an auto trans this is a pretty straightforward swap right? Any additional things I should replace at the same time?

Current box has about 10" of wheel slop right now. Definitely needs to go.
 

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10" of slop?!!!!!!! Maybe the system should be checked!
 

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This is the motion ratio between the input shaft and the output shaft. In the real world 20:1 is about 5 turns lock to lock ("Quartermaster, three points to starboard!" "Aye, captain!") while 16:1 is about 3 turns lock to lock (a reasonable and typical number for a medium-size car) with stock-length steering arms.

Some people think faster is better, but unless you've got something the size of an S2000, larger or softly-sprung cars can be horribly twitchy and uncomfortable to drive if the steering is too quick, the classic example of this is the '90-92 Infiniti Q45 (4200lb sedan with 2.1 turns lock to lock, very difficult to drive smoothly, they finally slowed the steering down to a reasonable 3 turns in '93.) There's guys out there putting 12.7:1 boxes in big old Chevelles and GTOs and unless they're building super-stiff autocross cars...well, the new GM boxes have great valving but I figure those still aren't going to be particularly nice cars to drive in the real world.

I've got a 16:1 Borgeson box with repro GT350 quick-steer idler and pitman on my '65 I'm finishing up, it's looking like about 2.4 turns lock to lock (need to get a better measurement with the steering stops in) which is about the same as my '00 M5. Should be okay in the Mustang, which is pretty tightly buttoned down, but we'll see how the bumpsteer and ackerman measures out with the longer arms, too.
 

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Discussion Starter #4
10" of slop?!!!!!!! Maybe the system should be checked!
Its mostly in the box and a little in the worn out joints in the steering. Its manual steer already so no power steering system to check. After driving it on the road once and hitting a few pot holes I haven't taken it out since. Whole new meaning to bump steer.:shocked:
 

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Steering

Know how you feel. I recently but in a 16:1 flaming river box in mine as it was scary to drive with the slop.
 

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10" !!!!!!!!!!!!!!!!!!!!? My 68 vert (sig pic) has far as I know original power steering components. Got it in 77 so can verify the last 34 years! It's had the normal tie rod ends, idler and ball joints over the years. I've personally greased and adjusted the steering box. With the engine running there is about 1" movement left or right before the wheels move.

Slem
 

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Discussion Starter #8
I've changed all the suspension up front, upper and lower control arms springs & shocks. Planned on steering box and all steering linkages next. Basically an entirely new front end. When I got it 3 of the ball joints were completely busted. Everything was original equipment from PO and very worn. Safety first.

So for the ratio I'm thinking 20:1 for smoother turns, less sharp and erratic response?
 

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With that much slop I would be looking at the ball joints in the center/draglink for wear.
I'm sure 10in of slop is an exaggeration.

But factory manual steering at 5+ turns lock-to-lock is so slow that the first five inches of travel in either direction might as well be slop, and I have never (out of approximately a dozen and a half cars) ever driven a Ford linkage-boosted power steering system that had less than 2-3in of built-in slop on center - in Mustangs, Falcons, Fairlanes, Galaxies, etc. It's just the way they're designed - the valve being on the output side of the steering box means that valve motion is multiplied by the motion ratio of the box, so for an equivalent amount of valve movement you're going to have 16-18x as much steering-wheel movement.

My '64 Country Sedan was the best of the bunch, and it was still pretty bad by modern standards - I've never driven a Falcon-chassis car that was much better than awful.
 

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Discussion Starter #11
I was working on my car this afternoon and jumped in it to check out the slop. Its about 60-70°. Either way, its getting replaced.
 

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I'm sure 10in of slop is an exaggeration.

But factory manual steering at 5+ turns lock-to-lock is so slow that the first five inches of travel in either direction might as well be slop, and I have never (out of approximately a dozen and a half cars) ever driven a Ford linkage-boosted power steering system that had less than 2-3in of built-in slop on center - in Mustangs, Falcons, Fairlanes, Galaxies, etc. It's just the way they're designed - the valve being on the output side of the steering box means that valve motion is multiplied by the motion ratio of the box, so for an equivalent amount of valve movement you're going to have 16-18x as much steering-wheel movement.

My '64 Country Sedan was the best of the bunch, and it was still pretty bad by modern standards - I've never driven a Falcon-chassis car that was much better than awful.

As I stated above my 68 has about 1" movement of the steering wheel before the front wheels move. That's as you describe. +/-1"=2" total. No one has to my knowledge said this system is precise like rack and pinion. IMO many people/mechanics use it as an excuse for poor set up/adjustment. The steering box is designed to be tight on center so the "slop" should be mostly because of the control valve.

If the front end is properly aligned a car should track straight no hands. Steering correction would be because of wind gusts, pavement ruts etc. Yes the other systems are better/more precise but the other systems poorly set up, aligned wrong can require frequent steering correction.
 
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