Power Steering box , not sure if it is a clever question...

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OK so I read the tag of my steering box - SPA-AE, which I see is a constant ratio @ 22:1. I plan on getting the Red Head quick ratio power steering box @ 12.7:1 . My questions are there any other changes I will need to make to install in my long nosed Mustang? Is the Red Head box a constant or variable ratio box?
On the Red Head box, I can't answer that because I haven't got one, but I would think it's a fixed ratio. Your SPA-AE box is NOT a 22:1 as that would be a manual box not a PS box. SPA-AE is a 17.5:1 ratio. >1/2/73. I think you just looked at the wrong line. The manual box tag for the 73 would be SMA-T @ 24:1 ratio. (according to my Marti Tag book.)
 

giantpune

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I'm finally getting around to doing something with my leaking PS box. The car is a 73 mach1. Tag on my current PS unit says SPA-S. According to the picture on the previous page, this one is listed for a 72 car. Somehow it ended up in my 73. I have 4 complete turns to my steering wheel.

I'm looking at the red head units. If I'm seeing their website correctly, they offer 2 options for our cars. The only difference I'm seeing is the 3-turn and 4-turn.
Are these all interchangeable parts, except for the gear ratio? I dont want to get stuck having to hunt down new hoses or adapters or fittings or anything.
 

Hemikiller

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I'm finally getting around to doing something with my leaking PS box. The car is a 73 mach1. Tag on my current PS unit says SPA-S. According to the picture on the previous page, this one is listed for a 72 car. Somehow it ended up in my 73. I have 4 complete turns to my steering wheel.

I'm looking at the red head units. If I'm seeing their website correctly, they offer 2 options for our cars. The only difference I'm seeing is the 3-turn and 4-turn.
Are these all interchangeable parts, except for the gear ratio? I dont want to get stuck having to hunt down new hoses or adapters or fittings or anything.

Box probably went bad and the PO swapped it for what was available at the local junkyard.

You'll want the quick ratio option, the 3 turn. They may keep a bit of the core charge if you return a 4 turn, but it's a night and day difference. It should bolt in place and use the original hoses.
 

Bentworker

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It is worth mentioning Lee power steering offers a larger torsion bar in the control valve. That will make the steering have more feel / feedback. That combined with a quick ratio is a heck of a setup.

If you just go quick ratio you will still have over assisted “pinky finger” effort.
 

giantpune

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I'm about to pull the trigger on the red heard gear box. Lady on the phone said no problem ordering the 3-turn model and then returning a 4-turn core. They're the same price, so they won't deduct from the core.

I haven't done one of these before. I think its fairly simple getting the hoses disconnected from the top side and the 3 bolts attaching it to the frame. Then a castle nut connecting it to the steering linkage. When its free, I think I have enough clearance there to drop it between the frame and the header.

What I'm not sure about is how do you take the steering gear loose from the steering column? There's a lot going on right there in the few inches between the firewall and the steering gear. Rag joint and power brake booster and all. Its pretty crowded. I just want to make sure i'm pulling it apart at the correct spot.
 

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There are two nuts that hold the rag joint to the flange on the steering column shaft. IIRC they are 1/2". If the joint is in bad shape, you may just rip them right out of it. Once the box is down, there's a through bolt on the rag joint clamp. It's a 7/16" 12 point, take it completely out, as it rides in a channel machined in the steering box shaft. You'll want a new rag joint, or to rebuild yours.
 

vintageman

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If you have a non-tilt column and decide to buy a new rag joint, RockAuto is where I got mine, Lares 201. Some of the other ones I tried had pins that were too short.

Tom
 
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If you have a non-tilt column and decide to buy a new rag joint, RockAuto is where I got mine, Lares 201. Some of the other ones I tried had pins that were too short.

Tom
Absolutely the Lares 201 for non tilt columns. Don't be put off by the pin diameters being the same versus the originals. That was only for assembly on the line. The pins are the correct length.
 
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Adding if you need room, you can collapse the steering shaft some at the rag joint to pull the unit straight down.

the part that bolts to the rag joint is a double d slip fit into the part where the steering wheel bolts to. It is tight, but they do (should for personal safety) move all the way up to the steering lock arm.
 

dees71mach1

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I had my 71 Mach 1 351 Cleveland original PS pump rebuilt by Chip Woyner at powersteering.com. He did a great job and really knows his craft and these old pumps. He detailed the pump and I also selected the fast conversion ratio 12:1 ratio. The fast ration conversion made a huge difference in steering feel/play. He can be reached on 417-864-6676 (Springfield, MO).
 

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