Special Steering Rack Lock Stops

[chrisbeck]

I'm restoring a '73 Federal Special in the UK. I rebuilt the steering rack with a new RHD housing and Pinion transferring all the other components over. Now the rack is fitted to the new Spyder chassis it is apparent that the lock is wrong. It seems that RHD racks have stops fitted at both ends of the rack but the LHD racks have just one long tube on the passenger side. This drawing and parts list confirms this (I'm assuming the bottom 2 are Europa):
Can anyone explain why there is this difference between LHD and RHD? It is fixable by fitting a shorter lockstep on the passenger side and an additional one on the driver's side but can't for the life of me think why there is a difference.

[4129R]

I have done 7 using Triumph Herald RHD racks.

It should be 2 + 1/4 turns approx lock to lock.

What is the problem?

[chrisbeck]

For some reason, the rack is located differently in the lhd cars. I spoke to Richard Winter today and he confirmed this. I measured up today and have to take 16mm off the single long lockstop on the passenger side and add a 16mm one on the drivers side. I have the correct lock-to-lock, it’s just the lock stops because the rack is located with less offset to centre line in rhd cars. Don’t ask me why!

[GavinT]

Yes, the alloy housing containing the pinion is positioned further away from the chassis centreline on LHD cars by about an inch.

On my RHD Type 54, the steering column is not dead straight ahead but points slightly toward the chassis centreline as viewed from the driving position.
Do LHD cars have this same feature?

I don't know why either but would speculate the difference between the LHD to RHD perhaps arises from the need to avoid a "sticky outie" component on the original vehicle for which the rack was intended - Herald or Spitfire.

[chrisbeck]

Spot on GavinT, in addition, the clamps are 1/2” closer together on lhd cars. This is confirmed on my new Spyder chassis which has drillings for both. Constantly learning!

[chrisbeck]

All sorted, after careful measuring I took 16mm off the long lock stop on the passenger end and fitted a 16mm one on the driver side. Everything is now centralised with tyre clearance to the anti-roll bar on full lock both ways. Track control arm pivots align with the top wishbone pivots. Everything will be accurately centralised when ride height set and toe-in adjusted.

[GavinT]

Well done.
Just in case you're unaware, there's a 'divot' in the rack shaft for the purpose of centralising it in the whole assembly.

[chrisbeck]

It’s just come to me! Because the pedal layout is the same for lhd and rhd (clutch-brake-throttle) the brake master cylinder is located differently and the rack has to be offset further to clear it on lhd cars.