Cheap Rack-in-pinion conversion

Discussion in 'Classic Mustang Specific Tech' started by sabersimon, May 13, 2009.

  1. I have a 1968 ford mustang with the old power steering. It is a coupe' with a 302 and long headers. I would like to take a rack-in-pinon setup from a newer car and put it on my car. I did a similar thing with my front disc brake setup. I have ranger rotors and s-10 caliper. Please Help.
  2. J-car rack.
  3. Even if you do this on the "cheap", it'll still cost you a lot more money and a lot more time than fixing the steering you have. If you don't like the power boost, and it's not for everybody, simply remove it and put a manual center link on the car, and you'll have 4-turn GT steering. Save all the PS stuff, though, the next owner of the car will want it. Your 4-turn PS box is probably in good shape, not much wear with power boost, most likely it needs a bit of adjusting, though. Use the procedure in the Factory Shop Manual, it's important to do the right stuff in the right order. This steering didn't suck, they were raced with it.

    zookeeper likes this.
  4. I've got my homebrew rack and pinion just about sorted out. I used a rack off of a 1992 Chevy Cavalier. Total cost so far $233.93. Projected total cost about $360.

    From the beginning of my 1970 Fastback project I knew that I didn't want to deal with the factory power steering system with it's leaks, on-center deadspot, wandering, etc. I also didn't want to pay the high price of the store bought rack systems. Besides, I like to build stuff and decided I could do it myself. So I did.

    First let me say that some of this design is my own and some is based on websites and pictures of other designs. I haven't driven the car yet, so it isn't road tested. I have no doubt in my mind that it will work, but I want everyone to be aware of the facts. I think that anyone that has some fabrication skill and can weld can build this system pretty easily

    The first step was to decide on which rack to use and off of which car. I knew I wanted a power rack and had to deal with the mustang rear steer system. A little internet hunting revealed that the GM rack and pinions used on cars like the Beretta and Cavalier was not only a good candidate, but has been used on the Mustang and is the basis for some of the store bought systems. I called up my local junkyard and they pulled a rack for me complete with the mounting straps.

    I then went about figuring how mount the rack. I decided to mount it like a website that I found that has since disappeared. I think that design is now being sold as the Steeroids system and mine is similar with a few differences. I had to pay attention to the angles that the u-joints would have to make to hook from the steering column to the rack. I also had to disassemble the steering column to shorten it. I then made the driver side bracket which is just a piece of steel angle and 2 pieces of steel flat stock. It took a few tries with modifications to the bracket to get the u-joints to work smoothly. After mounting this bracket and making sure the rack was level and ran straight side to side, I fabricated the passenger side bracket which is a piece of angle and a piece of flat stock.

    All that remained was to get it hooked to the spindles. I decided that I didn't want to mess with the factory steering geometry and thought that it would be rather convenient to just use the stock tie rods and center link. I cut the center link just outboard of the inner tie rod mount and positioned it where the factory system put it. Then I made a bracket that bolted on to the rack and welded the center link to it.

    The system works smoothly. The last items I need to do are finish weld the brackets, trim some excess from them, paint them and either make or have made some power steering hoses that will mate the factory pump to the rack. If I make some hoses using AN fittings and hose they will cost me about $125 more than what I have already spent bringing the total to about $360.

    All that I don't know is whether headers will clear. I figure since my setup is similar to the Steeroids system, the header limitations will be similar. I plan to use shorties or mid-length myself, but have some long tube headers I will give a trial fit. BTW my engine is a 351W.

    Here is what I have spent so far:

    Steering U-joints and DD shaft - $178.80 (Summit)
    3/4" ball bearing - $4.63 (for steering column)
    Steel for brackets - $5.00 (from local fabricator's junk pile)
    Misc bolts and nuts - $3.00 (hardware store)
    Salvage yard Rack - 42.50

    Here are some pictures:




  5. Randals rack & pinion...... great product, great guy.

    Very inexpensive for a system that's been engineered to bolt in easily.


  6. $1700 for a Randall's rack that uses the stock pump and steering column might be "very inexpensive" to you, but at least to me that's a lot of money. The Randall's setup does look like a decent product, but too high priced for me since I have some fabrication skills.

    Also to consider is that the Randall's rack is a custom J-car style rack. If something ever happens to it you have to buy a replacement from Randall's. If they are still around when that happens your good, but if not..... With a DIY J-car rack a replacement rack system is as close as the nearest auto parts store. I used a salvage yard rack, but a reman is only about $100.

    The aftermarket racks are fine if you are willing to pay the price and want a bolt in system, but the OP sounded like he had some fab skills and was looking for a DIY.
  7. Oh. Forgot to mention that once I have a chance to check header clearance I plan to post a more detailed set of instructions on how I did everything including drawings of the brackets I built. I will be initially checking with the long tube unknown brand headers that came on the car when I bought it. I am in the process of assembling my engine and once done will drop it in the bay to see if everything clears.
  8. Do you plan on beefing up the passenger side mounting bracket or are you hoping the the flimsy flat bar piece will hold it together?

    Just asking....:shrug:
  9. The welded centerlink makes me nervous. That has always been my issue with the homebrew racks. The forces imposed on that piece are tremendous and deflection is an issue that needs to be addressed.

    Your design plan is exactly what I was thinking of doing but the centerlink connection has me stumped.
  10. The side to side forces on the rack are taken solely by the driver side bracket. The passenger side bracket only holds that end of the rack to prevent fore-aft and vertical movement. The bracket you see is not totally done and will have a gusset, but that is all. It is made of 3/16 bar so it isn't exactly flimsy to begin with.

    Again, the picture you see were to get it mocked up. I may add some tubes to stiffen the centerlink up a little, but I really don't think it needs much. My reasoning is that all of the designs with the center takeoff rack really have the same problem. That is that whatever centerlink design is used it mounts to the rack with two 12 mm bolts that are only about 3 inches apart.

    Look at the designs that are out there:

    The unisteer rack uses a rather long and slender tube for the centerlink

    The RRS rack uses a long aluminum bar for the centerlink although it does have a support for the long end

    The Randalls system also uses a long bar centerlink

    The Steeroids system deviates from the long bar approach by using a bent steel plate affair for the centerlink.

    I really don't see much difference in any of the systems above except in the mounting brackets and in the way that the centerlink is handled. The RRS, Randalls and Unnisteer systems use long slender bars which is essentially what you find in a stock centerlink. All of the mentioned systems still have that problem of a centerlink mounted with 2 bolts about 3 inches apart. They seem to work, so I don't see why my approach wouldn't too.

  11. Please keep in mind that I am not bashing you. I am not an engineer. I am not a professional welder. I am just a hobbiest who lives in the land of the pothole also. In fact I am just north of you in Oswego.

    Every impact from those road craters will cause deflection. That deflection will put stress on the weld. If that weld breaks then you have a real problem. The centerlinks that the commercial companies have put together are not welded, they are machined. I understand that if welded properly the weld is stronger than the base metal, but the heat can change tension in the base metals. That's why I feel that a machined centerlink is safer.

    Just my .02
  12. I understand completely and I didn't take it as bashing at all. It was just an observation. I have given it some though and did consider reinforcing it a bit. I am an engineer, and was a machinist years ago, but this system is strictly "eyeball" engineered.

    My other option was to go with a square bar centerlink and machine tapered holes for the inner tie rod ends. That would have required an expensive reamer to do the holes. Ultimately, I looked at it from the perspective that the weakest part of the whole thing is the 2 bolt mount to the rack. Also the line of action of any force from the spindle to the centerlink is relatively closely aligned with the axis of centerlink. The component of that force that would try to bend the centerlink either up-down, or fore-aft, will be but a fraction of the total force. Below is a crude drawing showing what I'm talking about. The total force is the orange F and the horizontal and vertical components also shown. The horizontal component won't contribute to bending. The vertical component will, but is smaller than the total force.

    Attached Files:

  13. I was helping a friend change his pads and rotors on his wife's 2004 Dodge Durrango and noticed that it's got rear steer spindles with rack and pinon steering. I wonder if it might help get around the problem us 71 to 73 mustang owners have with putting a rack into our cars.

  14. well buy a used Durango rack and see what will work and what won't. i would like to say though, that you 71-73 guys really don't need a rack and pinion system as you already have the option of one of the best steering boxes ever made, the saginaw variable ratio box. this is the same box that GM has used in most of it's hi-po cars for years, monte carlo SS, Buick GNX, IROC camaro, etc, etc. you can get this box in ratios down to about 12:1, and there are a lot of top notch builders for these boxes as well, LEE maufacturing, AGR, etc. i believe there is even a new Delphi version of that box that is even better than the original. i can only wish we had the same choice in steering gears.

    in fact i like that box so much that i've been planning on grafting the frame rail section of big-body to a 68-71 ranchero (provided i can ever find one i can afford) just so i could be able to use that steering box. the big body cars are such a departure from the normal falcon/fairlane unibody structure though, that i don't even if grafting a frame rail section will even work, hopefully there won't be any problems doing it though, if i ever decide to do it.
  15. Seems expensive to me too when you consider you can go the AJE front stut setup for a little more money. That and you get much more adjustability on the front end. (dont start with me on the strut vs stock stuff, I drag race. heh)

    The other thing that sucks, Randall doesn't have a manual steer kit, of which I would want.
  16. 1700 is crazy Imo. heidts whole mII setup with disc brakes, tubular control arms, and a rack goes for 2000.
  17. blown65, I'm considering changing my manual TCP rack to a power one. PM me if you're interested in a used rack with not too many miles on it!
  18. Thanks for the offer, but I'm saving my pennies for the AJE front deal. Saving close to 100lbs and the ride adjust ability is worth it for me.
  19. I've got the Randall's rack, aside from the frame, centerlink, and the block that holds the centerlink, it looks almost exactly the same as the j car rack.

    I have a bad bellows boot, lists on rockauto for ~$28, looks exactly the same. Hell, I could probably do a little homework and put a new rp into the cradle for ~$90...

    I could be wrong, but it looks like most of the work in the kit is the cradle...

    I think the next time I need one of these, I'll make a copy for myself.
  20. With your Randals rack, how much turning radius did you lose compared to the stock unit?