It's a simple result of mechanical advantage. The higher the ratio (numerically), the easier it is to move the wheel, and more input at the wheel is needed to move the tie rods a specific amount. That means more steering wheel correction is needed when driving.

You'd like the combination of a 16:1 box and the Shelby Quick-Steer. It's a bit harder at slow speeds but, IMHO, great on the road.

 

Yeah, I was more wondering if anyone knows exactly how much different a 16:1 ratio is to, say, a 14:1 ratio (Borgeson) or even something lower.

I know I like the 16:1 box, I had one I'm not looking to swap out my rack and pinion anytime soon. If funds allowed, I would hook variable speed assist electric power steering to whatever setup I decided was best in order to achieve optimal road feel, steering effort, and ease of use. Jane does really love to destroy things, especially hydraulics, so eliminating one source of leakage would be helpful to me. BUT that's neither here nor there, as I'm not going down that road right now. I was just curious, that's all

I suppose I could find someone who has a 16:1 box and a Borgeson box and hijack their cars temporarily to do my own comparison... like that'd ever happen!! :lol::lol:

 

My 66 wagon came with the standard 16:1. I put a 14:1 in and it was a little quicker but not snappy. It didnt require as much movement of the steering wheel to do the same thing. I wish someone made a 14:1 worm and ball for the mustangs. Another thing that determines steering response is caster and sidewall flex. You can have the fastest steering in the world but if you have lots of sidewall flex the response will still be slow.

 

And let us not forget the diameter of the steering wheel has something to do with it too. A 15" wheel, 16:1 box, and Shelby Quick-Steer would be about the sportiest I would want to go for normal driving. Some of the options that are available to us are really best suited for Auto Cross duties and not for comfortable road trips.

 

most of the superspeedway stock cars use a 16:1 from what i have learned. at 200 mph you dont want twitchy steering. imagine a Smart Car at 200. :skullnbones:

 

Good post. The two things I want for my 69 Mach1 is a 14:1 conventional steering box, and a 14 inch diameter exact copy of the Deluxe Mach 1 steering wheel.

When driving the 69 it is so obvious these two things would be a great improvement. Borgeson (or someone else) could make a million sales with a drop in, conventional box with faster gearing.
Same with a good 14" steering wheel. double bonus for more leg room.

 

I have 16:1 box in my car, I removed the power steering. I have 205/60/15 in front, 3.5* caster and a roller bearing idler arm. It's not bad in parking and it's very easy on the road. I drove a friend's 65 many years ago with 19:1 manual and stock size tires, it was very, very easy to steer.

As long as you use a 15" steering wheel, keep the tires properly inflated and always have the car moving, even just a little bit is the key with manual steering. Power steering covers a lot of ills.

 

That's true. I have a 14" steering wheel with my 2.75 turns rack and I think it's perfect. But the power steering pump is a low flow model so it doesn't provide a ton of assist which keeps it from being overly twitchy. That is a whole different issue unto itself though related to the pump. But my car will haul through hairpin turn after hairpin turn at pretty substantial speeds without a lot of effort from myself - I mean that I don't have to spend 100% of my time spinning the wheel around and around, just turn it halfway one way or halfway another way and I'm good to go.

SA70coupe - not sure if they make this for '69s, but I know that Borgeson makes a 14:1 power steering box for '65/'66 cars. Might be something to look into!

 

I've been wanting quicker steering and to get rid of the hydraulic issues so I've been thinking a manual rack and electric assist would be perfect. However, the Unisteer manual rack is 4.5 turns. I see little benefit in a 4.5 turn rack over my stock 16 to 1 box. The TCP manual rack is 3 turns but almost twice the price. I guess I'll stick with the stock power assist and box for now and see what shows up in the future.

Rick

 

I have the manual Unisteer rack in my 66 and tho its BEYOND night and day difference from the stock setup in the fact that its tight and responsive and the car actually goes straight without having to steer like Im on a rally stage...you have to turn the wheel a million times to go anywhere lol. I dont mind it but wish the rack was closer to the 2.75 turns like the power rack. I daily drive a Focus ST which is 1.8 turns lock to lock so getting in the Mustang after driving it is rediculous lol

Matt

 

The Borgeson box is a 16:1. At least the ones I have seen. ABS makes a 14:1 ratio power box. 1964-67 ABS Power Steering Kit

That said, it is important to keep in mind that the steering ratio and turns lock to lock are not the same thing. The ratio effects how quick the steering is while lock to lock is how far the wheels will actually steer (turning radius). They are directly related though and do effect each other. For example, stock steering is 20:1 and has 5 turns lock to lock. With the same box and only 3 turns lock to lock the turning radius will suffer greatly but with a 16:1 box that does 3 turns lock to lock the turning radius will be similar to the 20:1 5 turns. Does that make sense? Quicker ratios don't need as many turns of the wheel for the car to turn the same amount as a slower box.
Steering wheel size also has nothing to do with turns lock to lock but a bigger wheel will be easier to steer than a smaller one.

 

That said, it is important to keep in mind that the steering ratio and turns lock to lock are not the same thing. The ratio effects how quick the steering is while lock to lock is how far the wheels will actually steer (turning radius). They are directly related though and do effect each other. For example, stock steering is 20:1 and has 5 turns lock to lock. With the same box and only 3 turns lock to lock the turning radius will suffer greatly but with a 16:1 box that does 3 turns lock to lock the turning radius will be similar to the 20:1 5 turns. Does that make sense? Quicker ratios don't need as many turns of the wheel for the car to turn the same amount as a slower box.
Steering wheel size also has nothing to do with turns lock to lock but a bigger wheel will be easier to steer than a smaller one.

Hmm, that does make sense. In this post though I'm essentially pairing steering ratio with turns lock to lock based on preexisting systems and assuming that turn radius is retained. But I guess, in hindsight, there's no real comparison simply because there are only two boxes (20:1 and 16:1) and the rest are racks which have a different feel to them.

In a manual steering setup, a bigger wheel will be easier to turn than a smaller wheel, yes. In a power steering setup, a smaller wheel is nice to have because you feel that you are jerking it around less (you're moving it the same amount, but it feels like less movement just because the wheel is smaller) and you already have assist so you don't need a bigger wheel for leverage. So to me, a smaller wheel on my power assist setup makes it feel more precise because you FEEL that you aren't moving the wheel as much to get the same amount of response.

Here's the link to the Borgeson 14:1 box for '65-67 Mustangs - not sure if it came out recently maybe? I just found it while I was surfing around the other day and that's kind of what got me started on this whole "wondering" thing. It's dangerous to wonder!

 

It definitely does seem like there should be some "perfect world" steering setup! It seems to me that the optimal power steering setup (great steering, no hydraulics to take up space) would be one of two things:
1) A short shaft 16:1 manual box, Shelby quick steer, stock steering linkage, and electric assist on the column.
2) A manual TCP rack and electric assist on the column.

Option 1's benefits include reliability, relative simplicity, ease of fixing (less parts to destroy, easier to get them, no long wait for a company to rebuild something for you if it breaks), full steering radius, guaranteed fit. But it is more turns lock-to-lock at 3.75 turns. However, it may be the best for the cheapest.

Option 2's benefits include guaranteed fit, full steering radius (I think), modern precision, less turns lock-to-lock (3 turns). But if you break something or something wears out you have to send it back to TCP. And a TCP rack PLUS an EPAS unit would run you way north of 3 grand.

I've no idea whether a rack or a box has better road feel / steering precision / sharpness. And I've no idea how much difference 0.75 turns makes in how "quick" the steering feels. That's what I'm curious about. Kind of makes me want to pull the Unisteer rack and put my old 16:1 box back in just to find out. But of course I'm not that crazy - I remember how much effort it took to pull the dang long shaft box in the first place :lol:

 

I hear ya on the TCP rack price! They have a very nice product and have every right to charge what they do for it, but I just can't foot the bill. The other problem with it for me is that my car is a daily driver and Jane likes to trash things, especially when they are very expensive. If it can break and can't be replaced at an auto parts store, it WILL break. If it can be replaced at an auto parts store (or by a place that is constantly in stock with sub-2-day shipping), it won't break. Silly, really, but that's how it is. So I have a very high motivation to NOT put it in simply because I know my car will destroy it and I'll be out of a driver for a few weeks which is not cool in my books.

Bump steer is caused by an issue with steering geometry - basically the steering geometry changes when you go over a bump to the point where it will jerk the steering wheel around if it is bad enough. Not a cool problem to have!

 

I typically hear a lot of people speak about the "modern precision" or R & P steering and the "tightness" of the steering. They most likely have never driven a Mustang with its manual recirculating ball steering box that's properly adjusted and with good steering components. If my wheel has 1/16" of play, I'd be surprised. Tight as a drum, responsive as all get-out and doesn't wander. One hand on the wheel into the triple digits.

I have to snicker..... rack and pinion was introduced to the US in the '51 MG. It was in use in Europe before then. Recirculating Ball was relatively new at that time as well, having replaced the simple worm and sector boxes. Currently, the BMW 850i (as well as some other vehicles...Jeep Wrangler is one) STILL use the recirculating ball steering gear due to its strength. US automakers started using R & P because it's CHEAPER, not better.

 

I typically hear a lot of people speak about the "modern precision" or R & P steering and the "tightness" of the steering. They most likely have never driven a Mustang with its manual recirculating ball steering box that's properly adjusted and with good steering components. If my wheel has 1/16" of play, I'd be surprised. Tight as a drum, responsive as all get-out and doesn't wander. One hand on the wheel into the triple digits.

all my manual steering mustangs have ben tight. if the steering linkage isnt worn our and the box is good and properly adjusted it will be tight unless you have flexawall tires. last year i put what was suppose to be better tires on my F350 truck. the steering response was slow and it wasnt as stable. i took it back and had them put a new set of the same that cam off on and steering response is quick. slow steering response is not always the fault of the steering gear > tires and also the lower the tire pressure the lower the response. thats called transient handling.

 

I'm definitely not knocking the rack setup or the box setup. I never had any issues with my 16:1 box and it was TIGHT with no play at all in the steering wheel. But I don't remember exactly how it compared to the rack in terms of feel. Neither the rack nor my old box were prone to making the car wander or feel unresponsive, ever. I suppose that if both connect the tires to the steering wheel then they should feel the same with the exception of inherent increased responsiveness due to fewer turns lock to lock in the rack.

It would be quite cool if there was a 14:1 manual box made for our cars. The Borgeson 14:1 box is power only. But I guess there's probably a reason that a 14:1 manual box isn't made.

 

Well, not one purpose-built road race car has RB steering, that should tell you something. Granted, weight and packaging are also factors, but if a RB steering was of benefit to the driver, they would find a way to fit it. It's certainly not because of the cost in this case.

Having said that, I would love to drive both systems back-to-back for comparison, but that's not likely to happen !

 

I was on the phone this morning with Dan from Chockostang (buying a set of 70 spindles and fittings to upgrade my 69) and asked about the options for increasing the steering ratio for the stock power steering. I was looking for the magical faster worm gear, but he assured me there is no such thing.

I worked through some posts about quick ratio boxes and Shelby stuff, and it seems the Shelby quick ratio will not fit a stock 69 or 70, and certainly not with stock power steering.

Just curious, I rang Lees Power Steering in Missouri about the same question (faster steering with stock 69 power steering) and he said "No". But he did add some interesting information. One option to increase steering speed is a reduction box, which basically converts steering effort at the wheel and shaft into faster speed input at the steering box, and there fore, faster output to the pitman arm. He said the problem with the 69 is there is just no room to install one. The bottom of the box is deep into the spring pocket and the top is almost on the firewall. So, no luck in that direction.

Seems a shame there is not a simple internal parts swap available. I like to keep the cars stock, but would also like to improve some annoying flaws, to improve the driving pleasure, and performance. Safety too, I guess. My 70 coupe has had a R&P swap, and a 14 inch wheel, and it is a peach to drive. I recently took both cars to a rad race track for a few laps, and the faster steering 70 was so much better to drive. Both cars have the exact same alignment specs. It is the steering that is radically different.

I will live in hope. If I were smarter, or an engineer, I would know where to go from here. It cannot be impossible to design and build a faster worm gear, or output shaft, or both. Someone will make a small fortune on the upgrade and rebuild market with a 14:1 or 12:1 ratio for a stock PS box.

 

I hope to accomplish option 1 this winter. I also agree that your 2 3/4 turn system needs to be normalized to a ratio to be apples to apples. You might be more like 3 or 3 1/2 turns if the radius were similar.

As for EPAS, ive been very happy with the road feel of my system.