Front shock absorbers

[Hugo]

I'm getting to the stage where I'm shopping for front shock absorbers - any preferences out there? Koni? GAZ? If past experience is anything to go by we'll get a dozen different preferences with no agreement anywhere!

[Series1 Stu]

Like many things, shock absorber preference is subjective. Hence the likely diversity of opinions.

What I would say is that Koni and Gaz are well made. Most of the others are less so. If you buy adjustables then you stand a chance of getting something you are happy with.

Regards

PS I bought Gaz, front and rear.

[Hugo]

Thank you - that's the way I was leaning - can the Konis be adjusted in situ? I believe the GAZ can?

[golfnut324]

Hi Hugo,

I have GAZ shocks set 6 clicks from the softest setting and really like the ride. FWIW

[chrisfell]

OEM as supplied by the usual suspects. +50,000 miles, and no problems. They've coped with spirited driving, heavy loads, mountain passes and bimbling along leafy but pot-holed lanes.

Imho, adjustables are required when the use of the car is likely to be variable, i.e. Sunday driving one weekend, competition driving the next. For all other occasions, the standard setup is perfect.

[christopher storey]

Make absolutely sure that whatever you get will not extend to a length between centres of more than about 405 - 410mm. There are various threads on here which deal with this - the consequences can be serious, as I had a track rod fatigue fracture as a result of the dampers extending to 430mm and thus allowing the track rod to act as the stop for downwards movement of the wishbone

This is the original link viewtopic.php?f=3&t=1326&hilit=fatigue

[Hugo]

Thanks everybody - I'm not going racing or rallying but I like the idea of being able to adjust the ride. That's a good point Chrisopher about the 'angle of dangle'. Actually that's given me an idea - I am in a good positionn to measure the 'drop' on my suspension; I am just about to fit the upper & lower wishbones to my car, but not the torsion bars as the engine is out. I think I will nip up all three tapers & see how far the suspension drops under its own weight - then I can measure the distance between shock absorber mountings on my car & see if they tally with yours. It's a bit unfortunate that the first thing to 'bottom out' is also the weakest - I heard they use high-deflection ball joints in the track rod ends. Not high enough by the sound of it.

[mgcjag]

For quite some time track rod end ball joints with not enough angle were the norm supplied by the usuals this resulted in pressure on the steering rack especially the ends if the front end of the car was jacked up..after a lot of discussion on this forum a slightly shorter damper ( Gaz adjustable) was introduced by SNG to restrict the suspension drop......continual research pointed to not enough angular movement of the track rod end (trs)..SNG were instrumentsl in haveing the tre,s re manufactured to give more angular movement to match original equipment measurements.....they are now widely available....but you need to ensure you ask for tre,s with wider movement....lots of info here if interested..its a very long thread Steve
viewtopic.php?f=3&t=6145&hilit=Tres

[Series1 Stu]

It's interesting to me that Jaguar designed the suspension without a proper bump stop on extension. Relying on the damper to do this is very shoddy.


Regards

[Hugo]

That's exactly what I was thinking. A bump stop under the top arm would be nice. Also it occurs to me that this situation would probably never occur under normal driving conditions. If you go flying or jack the car up, however, it might cause a problem - but this would probably take a very long time to manifest itself - if it ever does. So there are probably lots of cars out there where the ball joints have been necking and the owners are blissfully unaware of the fact. If and when they finally fail, however, it could be catastrophic and sudden.
Christopher Storey - I think I mis-understood your issue; having read the other links I gather it was your INNER ball joint that caused the problem - I read 'track rod end' instead of what you had actually written, which was 'track rod'.

[politeperson]

Hugo,

I fitted the cheap, standard Boge units that SNG supply front and rear. I also have the standard non-hard bushes all round.

The roads around here are awful.

This setup gives an excellent ride and are still in tip top condition 4,000 miles later. My car is really comfortable over bumps. Surprisingly so I would say for an E-type FHC.

If I had one criticism of my new "standard" rear suspension, it bottoms out too easily sometimes. I think my new rear springs could do with 20 lbs more push. Maybe I shouldn't have been so hasty to bin the old ones, fool me.

[Hugo]

You could fit spacers?

[Series1 Stu]

I think my new rear springs could do with 20 lbs more push. Maybe I shouldn't have been so hasty to bin the old ones, fool me.

Can you fit some spacers between the springs and their seats to give a bit more preload on the springs?

Regards

[politeperson]

I could fit spacers but I do like my ride height.

Anyway, its basically ok.

[christopher storey]

Christopher Storey - I think I mis-understood your issue; having read the other links I gather it was your INNER ball joint that caused the problem - I read 'track rod end' instead of what you had actually written, which was 'track rod'.

Yes , it was the rod that snapped next to the rack ball joint. Since we lost the photos that is not clear, so apologies. BTW, we reach full downward travel in normal cornering much more often than one might think, as the witness marks on my newly rebuilt car showed where the rack had been levered upwards by excess extension, in only 60 miles from total rebuild

[Hugo]

Upwards? What would make the rack go upwards? Unless you push on the tie rod (track rod if you prefer) when it's at or approaching full droop? And I can't see how that would happen, as the one that has the most drop would be on the inside of any curve? Am I missing something?

[Series1 Stu]

Yes Hugo, you are exactly the wrong way round.

The car leans into the corner so the outer wheel's suspension unloads therefore the wishbones drop. This in turn will force the inner end of the tie rod upward thus moving the rack up with it.

Ok?

Regards

[Hugo]

How on Earth do you make a car lean into a corner? I actually have a car (well, a three-wheeler actually) that does exactly that - it's a Carver One, which has a clever hydraulic tilting mechanism which makes it lean into corners. Other than that, anything with more than two wheels will lean outwards. It's called centrifugal force.

[christopher storey]

Exactly, Hugo. The car leans down on the outside wheel and the inner wheel drops to full droop surprisingly often, particularly if the car is going over a crest at the same time

This was the witness mark - it is under the bolt below the exposed rack in the picture ( this was the unfractured side )


and this was the fracture

[Hugo]

But... the inner track rod will 'droop' when cornering because the car is lifting off the suspension on that side. The maximun force on the rack mountings will be from the OUTER track rod. That force will tend to push the rack upwards, but less so than the inner track rod. The outer track rod will be more horizontal in attitude but will be applying more force to the rack mountings.
I am not convinced that your witness marks occurred because the track rod was at 'full droop' or anywhere near it - more likely they occurred when the maximum force was applied to the steering, which I would guess happens when you hit a pothole or similar when cornering.
Also, in the absence of power steering, there is the twisting force of the pinion to consider, at least if you're heaving it out of a parking space. That will probably be enough to make the rack shift a bit.
My car is in bits at the moment so I can't look at the track rods, but they do 'droop' a bit in normal driving, don't they? If they don't, my theory goes out the window.