Torsion Bar (single adjustment)

[Philk]

We have just had our IRS overhauled on our LHD 3.8 OTS (which has taken its central ride height back to where it should be at the rear of the car). However, the car still lists to the nearside (left) front corner (we have a 3/4 inch height difference between front left and front right which then translates through to the rear offside being higher). This is doubtless down to the car being LHD and the Torsion Bars which, for some reason, we did not get replaced last year when we had our front suspension work done . These are likely to be original with 98,000 miles now under their belt.

A question for all of those who've gone through this before.... Can one torsion bar be independently adjusted from the other or, at this point in their life, would it be better to get them replaced with new. My only concern with the latter approach, is that I can only find "uprated" torsion bars being sold through the usual suppliers.

Many thanks!

[mgcjag]

Hi Phil....yes they can be set/adjusted independantly..the procedure is in the service manual..its not complicated and you will need to make up setting links......as you suspension has been overhalled recently there should be no siezed parts so making it even easier.....go with what you have.....you can always change later if need be..Steve

[abowie]

As you have said you have a couple of options but all of them do have a downside.

You can keep your weakened TB and adjust it to match the other. Essentially you would need to lengthen the setting link you use so that when under no tension the lower wishbone points down more. The problem here is to know just how much longer you want the link, and I think that this would end up being pure trial and error which would be irritating. In your situation fitting an adjustable reaction tie plate might be a good option as it would make fine adjustment easier. Caveat: I have no idea whether "over adjusting" a weakened bar makes it more likely to break.

You can just buy a new set of TBs. The problem here is that I don't think that the replacements are the same diameter as your original 3.8 ones which may make setup difficult. Additionally, new TBs are quite expensive.

You could buy a used TB and see if it is any better. Problem is that you don't know until it's fitted and adjusted. I did this on my 4.2 and got lucky.

You could contact your local spring works and see if they can heat treat and reset both TBs. I have no idea if this is possible or not.

[Philk]

Hi Andrew

Many thanks. All of your points make considerable sense. I will explore whether it is possible to get torsion bars reconditioned. My concern with "tightening" up the Left Hand torsion bar by one spline is whether this will weaken the bar further by keeping it under higher load all the way though its movement range.

With regards to the new uprated torsion bars, does anyone know if these have the effect of making the ride less pliant?


Regards


Phil

[mgcjag]

Hi Phil...are you really sure your torsion bars are no good.......there are plenty of E types out there with your type of milage and original torsion bars with good ride height.......Why not just set the correct ride height then monitor over the summer and see if it drops.....It probably takes less than a hour per side to adjust....Steve

[Mich7920]

[ChrisC]

I would agree with that approach - its not hard to adjust and then keep an eye on it. Save the money for buying petrol

[Philk]

As an update, I finally went with the option of having an adjustable reaction plate fitted. As a result, the car is now virtually level (just a couple of mm difference in wheel-arch to ground measurement from one side to the other). Having had the IRS refurbished over the winter, things will undoubtedly settle at the rear over the course of this coming year's "season" so it's good to have the opportunity of further easy front adjustment further down the line.