Fox T-Bird/Cougar Forums

It is a very common misconception, that when you  lower your vehicle you will acquire a bumpsteer problem. This is completely  FALSE!

First a quick explanation of what bumpsteer is. Bumpsteer is a  curve or graph made from taking several measurements of toe change (wheel  pointing in or out from center) as the wheel moves up and down through its  suspension travel. We always want this change to be as minimal as possible (zero  is best) to prevent the suspension from "steering" the car when it hits a bump  in the road. This adds stability and safety to the car and has been designed  into the front suspension from the factory.

Changing the ride height of  the car will place the suspension in a different part of the bumpsteer curve,  although it will not change the curve itself. While the bumpsteer at this  particular point in the suspension travel may not be quite as optimal as it was  at factory ride height, it is typically fine for street driven  vehicles.

Now as soon as you alter the relationship between where the  steering rack, control arms, and spindles are located, as with the 96-98  Spindles, you create a completely different bumpsteer curve. This is when you  need a bumpsteer adjustable tie rod end to re-tune the bumpsteer curve on the  car.

For your application, and due to the complicated, time consuming  process of bumpsteering a car, I highly recommend against installing these  spindles. They are a lot more hassle than they are worth. I would try and find a  set of 1994-95 spindles that have geometry closer the your original  ones.

(http://picasaweb.google.com/ether947/Misc/photo#5041583103125654114)(http://i69.photobucket.com/albums/i78/ether947/misc/spindles.jpg)

In regards to your comment about bumpsteer, I think what you are  experiencing might be tramlining. This is the tire's tendency to follow ruts or  grooves in the road. It is typically accentuated by performance wheels, tires  and suspension modifications. It can be helped by a good alignment but it is a  side effect of adding more grip to the car, and is something that most  performance modified vehicles experience to some extent.

So if one were to, say, install a 96+ K-member in order to do a mod swap from, say, a Lincoln Mark VIII, one should use the 96+ spindles (and of course control arms) as well in order to maintain geometry?

If you're building a street car, or one that see primarily street use, like I mentioned, the bump-steer kits really aren't a good idea.  The geometry might be better when used on the appropriate K-member, but on a Fox? Not so much.  The "grinding" required is not required for the Cobra brakes....as the 94-95s used the same ones.  It's when you use the 11" 99+ PBRs that you need to do the grinding.

I'm not sure you can move the rack down 1".  You may start running into things (K-member), and the steering shaft might be too short. 
Dropping it, even if it's 1/2" would help though.

I don't think extending the wheelbase moves the P/S rack at all. That would screw up the ackerman.