Bad steering rack? Tvr Tuscan
Discussion
I’m a bit confused.
Have done a load of work on my Tvr Tuscan. New bushes al over, new ball joints, track rods, rod ends, rebuilt gaz monos, new pilot super sports. And a mod which is some safaris steering arms in an effort to reduce bump steer.
Had the geometry done at a well know place and generally it feels spot on, more compliant than before, tracks dead straight.
But.
The steering now doesn’t return to centre very well, it’s very slow, infact centrally it feels a bit dead. It also seems to wander and is worse when letting off the throttle.
I am sure that before al the work (I haven’t used the car for 3 years) the steering was very quick, too quick! And the rear end felt detached! Well now the back feels planted but the front is slow.
The rack did have a tiny leak, I used the recommended amount of Lucas stop leak, I do wonder if that’s thickened up the fluid? Making it slow.
I also had an issue when I tried to change the track rods, we couldn’t undo them and found a slight amount of play in the rack bar.
The specialist was given an open invite to change the rack if he felt necessary, but he said it’s ok.
I think the rack or linkages are troublesome though, steering should return to centre easily, this is like it’s delayed iykwim.
Or the geometry set up is out, but I don’t think it is.
Values are
1.5 neg front
2.5 neg rear
Max castor (it’s actually slightly less
0 toe front
24 mins total row rear
These are what I asked for as I had this set up previously and it was about right.
Cheers
Have done a load of work on my Tvr Tuscan. New bushes al over, new ball joints, track rods, rod ends, rebuilt gaz monos, new pilot super sports. And a mod which is some safaris steering arms in an effort to reduce bump steer.
Had the geometry done at a well know place and generally it feels spot on, more compliant than before, tracks dead straight.
But.
The steering now doesn’t return to centre very well, it’s very slow, infact centrally it feels a bit dead. It also seems to wander and is worse when letting off the throttle.
I am sure that before al the work (I haven’t used the car for 3 years) the steering was very quick, too quick! And the rear end felt detached! Well now the back feels planted but the front is slow.
The rack did have a tiny leak, I used the recommended amount of Lucas stop leak, I do wonder if that’s thickened up the fluid? Making it slow.
I also had an issue when I tried to change the track rods, we couldn’t undo them and found a slight amount of play in the rack bar.
The specialist was given an open invite to change the rack if he felt necessary, but he said it’s ok.
I think the rack or linkages are troublesome though, steering should return to centre easily, this is like it’s delayed iykwim.
Or the geometry set up is out, but I don’t think it is.
Values are
1.5 neg front
2.5 neg rear
Max castor (it’s actually slightly less
0 toe front
24 mins total row rear
These are what I asked for as I had this set up previously and it was about right.
Cheers
m3jappa said:
The rack did have a tiny leak, I used the recommended amount of Lucas stop leak, I do wonder if that’s thickened up the fluid? Making it slow.
A fluid leak or fluid viscosity doesn't affect the gearing of a PAS rack. It might conceivably affect the weight of the steering, but it can't affect its speed.My money is on the physical steering geometry changes you've made, ie the Sagaris steering arms being the cause for the different steering feel.
There is no guarantee these will make a Tuscan steer "better" as they were designed for the Sagaris front suspension which has I believe different wishbone pickup locations and a different rack height (TBC) and therefore the arc taken by the top/bottom ball joints and steering rack track rod end will be different to a older T-Car chassis. so just bolting these on without then measuring what the steering angles are through all wheel movement in bump and droop is more a hit and hop exercise that it will be "better". All just IMO and who knows you might have hit the sweet spot regardless.
There is no guarantee these will make a Tuscan steer "better" as they were designed for the Sagaris front suspension which has I believe different wishbone pickup locations and a different rack height (TBC) and therefore the arc taken by the top/bottom ball joints and steering rack track rod end will be different to a older T-Car chassis. so just bolting these on without then measuring what the steering angles are through all wheel movement in bump and droop is more a hit and hop exercise that it will be "better". All just IMO and who knows you might have hit the sweet spot regardless.
Very valid and I have been told by one specialist that he fitted some once and the car was worse.
But then I know of a few who have said it’s transformed the car.
One guy I know has said his has been tested back to back with a sag and it’s as good.
I might take it to someone with a hunter machine first just to rule out and incorrectly set toe or other settings.
Ultimately I want to take it to centre gravity where all of these different scenarios can be determined. But I don’t want to do this until I know the rack is ok.
But then I know of a few who have said it’s transformed the car.
One guy I know has said his has been tested back to back with a sag and it’s as good.
I might take it to someone with a hunter machine first just to rule out and incorrectly set toe or other settings.
Ultimately I want to take it to centre gravity where all of these different scenarios can be determined. But I don’t want to do this until I know the rack is ok.
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