Triumph Repair: Triumph Stering rack (in a TVR)

Question
I have a TVR Vixen 2500 (vixen body and frame with TR6 motor) This car does not have an M frame.
I recently replaced my steering rack mounts. And I need to make sure the rack in centered. Is there an easy way to do this?  I am not sure if this is a TR6 rack or a Spitfire rack.
For example if it was a TR6 rack I know (from literature) 8 inches off the steering shaft is the center of the rack.  
I need to know if I have a TR6 or Spitfire rack first.  and if it is a spitfire rack I need to know how to find the center of it (is it the same 8 inches from the steering shaft?)
Once I center the rack I will need to center it lock to lock. Is this done by just counting how many turns and cutting that in half with the wheels pointed front (and then take the steering wheel off and place it in the correct spot?)
thank you for the help.

Answer
Hi Larry,

Sorry, I don't know anything about TVRs. But I know how to center a steering rack. With the rack boots off just run the rack out to one end and measure from the end of the rack to the tie rod joint on the rack and then run it the other way and measure the other end to confirm that the rack extends out the same distance. If it does just run the rack in until the measurement between the rod ends and the rack tube are the same. Now mark with a magic marker or put a hose clamp on each side up tight to the rack tube so it stays centered and then measure from the end of the rack (not the tie rod) to any fixed point on the king pin or a ball joint and move the rack right or left until both sides are the same. Then clamp it there or make you mounts there if you are needing to make mounts.

If you are building the front end, you have to be careful as to the hight and forward of aft location of the rack mounting too. And you needed to get the langth of the tierods the correct length or you will have what is commonly caled "Bump Steer". Which means when the suspension is compressed the arch that the suspension moves must match the arch of the tierod movement.

Usually what builders do is to remove the spring so you can easily move the spindle up and down and all you have to do is to put the wheels on and spin mark the tires so you have an accurate scrib line on the tire. Then carefully check toe in at the bottom of the travel of the suspension and the top and the middle and if all three match with the same toe in you have it correct and will have no bump steer.

If your rack is already mounted and has no adjustment for position you can just count the number of threads on the tie rod end lock nut showing after setting the toe in to get them the same. Some British cars have a notch for the pinch bolt so putting the steering shaft on is set and not adjustable. After all is set on the rack and steering shaft and the steering wheel is usually only splined so the steering wheel then can be removed and set straight.

I hope this helps,

Howard