Can someone please check what I've done? Esprit S2 front suspension

[GTK]

Hey Steve, hope all's well.

I didn't even think about the knock on from which mounting hole I used, even though I noticed the two different holes before I put the damper in. I'll check it this morning with the damper in the lower pair of holes. The other damper has never come out of the arm because it's seized in so it'll be interesting to see which pair of holes it's mounted in.

I'm not with you in terms of where you're measuring the damper, the hole centre of the bottom mount, sure, but at the top? Are you measuring to the tip of the ram at full extension? Basically I don't know what the isolator perch is?

 

[drdoom]

Getting along well enough mate, thanks.

As to my term, " isolator perch " it pertains to the pair of rubber cushions ( isolators ) that function to make a compliant joint between the steel stud of the damper and the chassis turret to which the damper is attached. With some dampers of this form there are a loose set of cupped steel washers to help retain and locate the rubber bits around the stud, whereas the OEM Armstrongs have that lowest of the set welded integral with the stud. I measured by eye with a steel tape, the damper fully extended ( i.e. suspension in droop ). Would have included a photo but the bleeding camera wouldn't pull focus on the tape close up, attached one taken just now which I hope will illustrate the unclear aspect. So, 342 - 343mm from bottom bush C/L to the upper surface of the washer, or "perch", seen concentric with the stud.

Cheers

Cheers   

[GTK]

 

It's great that you had that to hand!

I realised later what you meant, and I've had a chance to measure the aftermarket dampers that came with mine since. Couple of observances too, first that the hole centre on the bottom of the damper is offset on the vertical plane, so the measurement from one side will be slightly different to the other side. Also that my dampers were attached via the upper of the lower arm bolt holes, so definitely not the ideal in terms of the lower arm total travel.

I'll add a few pics I took. My Gabriel dampers [which someone suggested were common after market back in the '80's/early '90's, were definitely too long. They measure 355mm or 360mm [depending on which side you measure from] and give or take a mm, using the same reference points as you used, at full extension.

I extend one of them to 343mm and marked the lower body of the unit so that I could then mount it to the chassis [in the lower mounting holes] and accurately extend it to that length. Then checked where the lower arm was in relation to the bottom plate of the chassis shock tower.

It was *just* touching the bottom plate. I've had to straighten my bottom plates and it's possible that they could be sitting slightly high. If they are, it's not by much, I'd be suspicious about whether the bottom arm would still hit under a heavy bottom out situation that deflected the damper bushes. Anyway all's well that ends well for now. Good to know to be exacting about damper length.

I have a set of low miles Pro Tech adjustable dampers on the back burner, that I'll measure for ref, when I am able.

 

[drdoom]

Very good with your response George. Though in agreement on taking care in regard to bottoming out of suspension travel are we not looking at the opposite here? If suspension is driven into full compression by way of some epic joyous motoring ( oh speed that happy day! ) would we not expect the lower TCA to have gone to its furthest point of separation with the turret bottom? Critical to managing impact stresses of full compression are the rubber cushion between damper and underside of the turret top and, not as obviously, bump cushions unseen but present within the shielding tube surrounding the damper piston rod. As the Koni's shown in the attached photo are, like your Gabriels, without the shielding tube I've added a supplemental cushion atop the damper body for peace of mind. 

I see that the difference in length measured one side of the Gabriel lower bush as compared to the other is clearly due to minor derangement of that bush, result typical of deterioration but not a factor in my example.