Help with front suspension travel?

Hi,

Can anyone with a 4.0 Facelift with sportspack shocks and springs help me out with some idea just how much up/down travel I should expect when I push down on the front of the car?

I’ve looked in my workshop manual DVD but can’t easily find the specs for this.

I recently had the front springs and shocks replaced (the previous springs were the 24 year old original and the shocks about 10 years). Bouncing the front suggests no problem with the shocks. Car rebounds and settles in a single bounce. But I suspect the springs are too stiff, possibly I got a V12 set by mistake despite ordering the part number correct for my model. The ride height looks good, being about 1" - 1 & 1/4" higher than before the change. But the vertical travel on the front is virtually non-existent and the ride over bumps is as harsh now as it was with the very tired and sagged old springs and shocks while I would have expected some difference.

The difference between you pushing on the body against the springs versus the cars weight operating against the springs is chalk and cheese, so I don’t think you can draw any conclusions from that test.
I would expect the sports pack to be slightly harsher than comfort but I haven’t driven the XJS fitted with sports pac in a very long time.

For sure,. Stiffer with new springs and new shocks than with weak old springs and poor shocks.

I know that somewhere in the lore the ride height is recorded and where to measure it.

It is for my XJ6. forgot what though.

Carl

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Especially these days, the consolidation of part numbers along with parts that are NLA I don’t think you are going to find very much distinction between the various models. The Aftermarket has seemed to reduce the offerings to more or less a one size fits all mentality. In some cases it’s even hard to find out who even makes the parts any more. I am acutely aware of your concerns because I am currently waist deep wading through and sorting out suspension parts for my own car and in some cases have found little to no differences if available at all.

Contributing to the scarcity of OEM parts is the drastic reduction in Jaguar parts houses, and of the ones that are left have even changed as well.

It seems like the more years that pass between us and the inception, the harder we strive to just get close enough.

It started a couple of decades ago, I think.
Dear departed and I assisted son in getting his
machine shop opened d equipped. One machine was to resize and straighten connecting rods doe reuse. One part a hone.
son had issues with making it “hold tolerance”.Ie, round and true to the axis.

The maker’s rep was brought in to “adjust and instruct”. Not much better, if at all. Rep’s pronouncement. “It is close enough for automotive work” Son’s response, “get that junk outta here”. it left, money returned.
Got another brand. Slick. still has it, but shop closed tools for occasional use only…

Now in on line sales of performance products. Some made in house by repurposed and updated CNC mills.

Carl

Great example of conformation Carl.

Whether you need them or not the best thing that any of us can do is to pick up random NLA spare parts that are spotted floating around from time to time because the chances of finding them again are probably slim to none.

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FWIW – there is a suspension and alignment TSB 60-5 latest update 1/96 for all models except XJ6 Series III.

states the setting height for all XJS front 6.00 inch plus/minus 0.2 at the bottom of the front sub frame to the alignment equipment wheel plates
states the setting height for all XJS rear 6.38 inch plus/minus 0.2 at the rear edge of the wishbone to the alignment equipment wheel plates

And of course these are specs for the car at mid-laden height and doing alignment work. But should be good ballparks for you

Thanks for all the replies. Using those specs the front ride height looks close if not an exact match.

I guess it is a hard thing to judge going only by memory. The degradation in performance of the old springs snd shocks is gradual and it’s hard to remember just what that ‘new car’ ride was really like after all this time.

There are also a lot more speed bumps on my route to work than there used to be 10 years ago!