TR4/4A TR4 Steering Racks

[mylesw]

Hello

I have a late (post CT20000) TR4. I am converting this car to RHD however I cannot find a TR4 rack. I can find a TR4A rack however. Does anyone know if it is possible to fit a TR4A rack to a TR4?

Thanks

Myles

 

[TR4nut]

Myles-

I just bought an LHD TR4A rack on ebay, when it comes in I can tell you if there is a difference. From the factory manual, however, I do not believe there is any difference on the rack itself as to mount locations, but if I remember correctly the total length of the TR4 rack including outer tie rods is slightly longer than for the TR4a. I thought they were 'close enough' to be useable, but I can't confirm that yet.

If you are getting rid of your TR4 rack, I'd be interested! Or possibly you could look at changing out the outer tie rods on the 4a rack and you may have a perfect RHD setup at that point.

Regards,
Randy

 

[Andrew Mace]

The early TR4 racks mount differently (more of a solid mount as I recall) than do the later racks (more typical rubber-bushed mounts). I'm not sure if the slight difference in rack design to accommodate one mount or the other is significant or easily dealt with when using a later rack on an earlier car or vice versa?

The Moss Motors online catalog shows how the two styles of mounts differ.

 

[trfourtune]

my understanding is that the end to end length of the RACK is different. Why are you converting to RHD. don't you like LHD in texas? are you moving to: england,australia,new zealand,japan????I have a LHD tr4 rack-highest offer takes.
Rob

 

[mylesw]

Thanks for all your help. Think I am going to get a TR4A rack and switch the ball joints as Randy suggests. I'll probably rebuild the rack myself too, seems to be pretty straightforward from some of the things I've read.

Thanks

Myles

 

[TR4nut]

Myles-

I looked at the 4a rack that arrived this weekend, and also the original manual specs. I am not sure if you need to even swap out any parts, the racks are very similar.

Here is a scan of what is in the original manual:

I have measured the mounting flange distances on the racks and they are identical. The only dimension difference that I see is the overall length. The TR4 rack is 0.13" longer on each side. I would think that there is enough thread depth on the tie rods to accommodate that difference. There may be a design difference in the lock to lock turns of the rack, but I doubt that will be that big an issue.

Regards,
Randy