TR2/3/3A Identification of Rack and Pinion Unit

I am working on my friends 60 Tr3 and am trying to identify the installed rack and pinion unit. From the paperwork that came with the car I can tell the mod was done some time in 1994. Robert Buerlein of Buerlein Motor Company and Bob Schaller of Schaller Engineering were involved. I suspect this is a cut down TR6 unit, but without a TR6, TR4 or Spitfire rack unit to compare it to I need some help from the experts here. I have included an image that shows the distance between the ribs near the hold down clamps to be 8" apart, the length of the rack housing to be 13 1/2" and the distance from the inner tie rod nuts to be 19 3/4". I do not know what tie rods were used with this set up.

This unit works very well with no detectable bump steer and 2 1/4 revs of the steering wheel lock to lock.

Any help identifying what the original rack unit was would be greatly appreciated!
Steve Baker

I have no idea, but I think when my brother did his car he used a TR7 rack, which is actually a better fit than the TR4-6 (narrower, believe it or not) so that is a possibility as well.

ISTR that the early TR4 rack had 2 1/4 turns lock-to-lock...but don't quote me on that!

I measured two TR4 racks and they measured 12 5/8" inside rib to inside rib or 13" outside rib to rib. That is short for your 13 1/2" measurement. I believe one of these came from a TR4 and the other a TR4 A.