Steering Rack Relocation

One of the rule changes for 2003 was the legalizing of steering rack relocation. Some cars had been running this previously and found that it offers a noticeable improvement in steering reponse, so spec racers now have the option to perform this modification. This page will assist you in completing the steering rack relocation.

Brief Overview
The stock steering rack location on the Factory Five roadsters is such that it produces negative ackerman with steering input. This means that as you turn the steering wheel, the amount of toe in is increased. By moving the steering rack rearward, positive ackerman can be achieved. This will primarily help turn in, and allow you to run less or no toe out.

Relocating the rack is relatively simple. I did mine while the front half of the body was off and the radiator was out of the car, making it very easy to access. You'll have to use your judgement to determine whats best in your situation. It could take anywhere from 3 to 6 hours of work depending on the car's current state, tools available, and type of rack being used.

The Process
Assuming you have already removed everything that is in the way, the first thing you need to do is drill the new holes through the upright 'X' tubing using a 1/2" bit. Use the existing rack mounting holes as a guide. The bit will need to be long in order to reach through the old mounts to the back side of the upright tubing.

Here is a tip when drilling the holes. Because of production tolerances, some cars will end up with the hole very close to the edge of the square tubing, or going through it, on the passenger side. You can elongate one or both of the existing mounting holes upwards so that when drilling through the tubing, the bit isn't trying to intersect the bottom wall of the tubing. This was necessary on my car.

The bushings for the rack will need to be cut down to fit between the upright and the old rear mounting tab. I'm not sure how this works out for the Flaming River rack, but for the Mustang power rack the bushings will need to be cut flush with the rack mounting ears. In effect, the complete flanged portion of the bushings will be cut off. You will also have to cut the metal tube that goes inside the bushings to match. Sorry, no pics of this step.

If you are using a power rack, then you will have to make a notch in the driver's side of the upright to allow the rack to sit back in the new location. The square tubing can be carefully cut using trial and error to get just enough clearance for the rack to bolt into its new location. Leave enough extra room to weld in metal pieces to box in the notch. You can see the completed notch below.

Now the rack can be bolted up. The bolts will need to be longer than the kit supplied bolts. Five inch long bolts work perfectly. The following pics show the rack bolted up in its new location.

With the new location of the rack, the intermediate steering shaft will need to be shortened. There is potential for a problem here in that the angle on the upper u-joint could cause the joint to bind. Keep the upper u-joint as close to the pillow ball bracket as possible to decrease the angle and avoid bind. This may require shortening of the main steering shaft, depending on how your car is set up.

Don't forget to realign the front end when you're done! Also, keep in mind that the tie rods will need to be longer now, so you might want to make sure you're not running out of thread engagement in your rod end adapters if you are using them.

This site contains pics and info as a reference to those building FFR Spec Racers, and anyone that simply has an interest.

The site will not be updated further as I have sold this car in early 2003 before the start of the race season.

Krichbaum.net
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Steering Rack Relocation