Robs Stupid '68 Mercury Cougar Section

This is Robs Stupid Cougar Page documenting the creation of rack and pinion steering for my 68 Cougar. It is Stupid.

Jun 14, 2002. I was driving my favorite car around and the steering got loose all of a sudden. No noise, no indication of why, just all of a sudden, I had very little control of my car, it had nearly half a turn of slack in the steering, which was very scary. I managed to limp the car home, going about 25mph all the way.

I spent all the next week trying to figure out what happened. It turns out that the steering box just decided to take a dump. When the steering wheel is turned, the shaft connected to the pitman arm that does the work would only move up and down until the wheel was turned nearly half a rotation, then it was semi normal. I tried to adjust the box, but it was hopeless, so out it comes.

After removing all of the stock stuff, I tore into the steering box. The top of the shaft appears to be held in place only by the adjusting nut that sticks out the top of the case, but there is a lot of slack in the channel that the bolt fits into. The bottom line is that it just wasnt readily fixable

I have been wanting to install rack and pinion in my car for a long time, but wanted to wait until the end of the driving season. I wasnt going to spend $500 to rebuild my steering box when i was just going to rip it out in a few months.

I definitely wasnt going to spend $2000 for a bolt in rack and pinion kit. Since you can buy nearly any rack for less than $200 and all you need is a couple of brackets and some ujoints, it amounts to spending $1800 for a couple brackets. To make it worse, the kit makes adjusting your front alignment very difficult since you have to replace your eccentrics with a plate that allows only very limited adjustment.

I read an article in a magazine about how someone installed a rack from a Taurus/Sable. This is the first thing I decided to do. As I started to plan how it would go together, I noticed from the pictures that the distance between the inner tie rods was around 28 inches. I didnt think much about it until I was under my car figuring the best way to hook it up. I noticed the distance between the inner tie rods on my 68 was more like 15 inches, this just would not work.

Here is a pic from the article. This would induce a dangerous amount of bump steer.

Since the lower control arms on my cougar are so long compared to the upper control arms, it would make my car a tad more responsive my separating the inner tie rod ends a couple inches more, but no where near double, you would be in for a surprise if you hit a bump while making a sprited maneuver.

I remember thinking that the rack in the rack kit looked a whole lot like an 87 Grand Am that I worked on once. The reason it stuck in my mind was because the tie rods connected to the middle of the rack unlike most racks that have the tie rods coming out of the ends. Someone mentioned that the kit was made from a 90s Corsica. Seemed very likely that they were similar.

June 23, 2002. I went to several auto parts stores looking for one that had a rack from a 90s Corsica in stock that I could look at. I finally found one, it looked just like the one from the GrandAm I was thinking of. Turns out it is even the same part number. This was just too coincidental so I bought it.

I used a couple jacks to position it approximately where I figure it should go, and it is going to work great. The angle of the input shaft is also nearly identical to the angle of the steering column shaft, albeit offset a couple inches to the right and down.

If I was to design a rack myself, there would be a couple things different, but this is easily modifyable to work perfectly. For one, I decided to mount the rack directly in place of the crossmember, but with the bolts toward the front, the straight bracket between the rack bolts and tie rod connection points wont be even close to straight, but wrap under the rack.

The only other thing that is not perfect, is that the hydraulic lines run over the top of the rack, which requires the rack to be mounted lower. Depending on the exact position, I may need to reroute the lines to go across the bottom instead of the top. No problem, just rather not have to.

July 2, 2002. Attaching a 15 inch wide bar to this rack for the existing tie rods to connect to just isnt going to work. The geometry would be right, but the strength just wouldnt be there unless I was to put some sort of idler for the bar to ride on. This is just too cheesy, would look crappy, and may have maintenance problems. I bit the bullet and got a new steering box to put my car back to stock configuration.

Normal steering forces would stress the rack in ways is wasnt designed to accept. When the car leans around a corner, it exerts a twisting force as shown in the picture below.

Regardless of whether you factoring in the body roll into the equation, it still exerts forces up and down on the rack as shown in the graphic below

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