Another ride height question

Hello All, I just finished my first swap. I put a 5.3 in an 86 XJ6. As expected, the nose is a little higher than it was with the older straight 6. I think I’m okay with the front hight of the suspension but I was wondering if there was a way to pick up the back a little. The back shocks are shot so they need to be replaced. I’m not sure if just replacing the standard springs/shocks will give me a little more height or if I need to buy a little larger spring. Does anyone have experience in this area?

Also, once the shocks are on, I would like to get the car aligned but that seems to be quite tricky. Supposedly, you need to rachet the car down to align and none of the local shops want to touch it.

Here are the questions I have:

  1. Where should I get rear shock/spring assemblies and what kind should I use?
  2. Where can I get alignment specs for an 86 XJ6?
  3. Does the rear need aligned or just the front?

Thanks for all of the help!


Hi Adam, I’m in the process of rebuilding my 1985 xj6 and will be putting a 1995 LT1 Gen2 small block in it. I have been at this build for 18 months and am happy to share what I have learned.

The front ride height is pretty easy (relative to other things) to adjust. There are “packing rings” stacked above and/or below the springs, they are just a tough nylon-type ring 1/8" thick. Adding or removing one equals 5/16" change in ride height. Another standard method of adjustment is to lower the bottom spring pan (seat) by placing spacers between the pan and lower A-arm; same amount of height change. My S3 came as a “glider” so ride height will be something I will address when it is all together. I have read posts that suggest the best looking ride height is one where the tire fills the wheel opening equally around, but depending on the tire size you use, that might not give the best ride height geometry.
In the back, there are fewer options to adjust ride height. Replacing bad shocks is probably the first thing I would do. Most all of the better shocks now are gas-filled and as such will exert 15-20lbs each of expansion force. 4 shocks then would be providing about 60-80lbs of lift to the rear without any other adjustments. If you don’t think that will do it, I have read that there are other springs with different ratings available for our cars, but opinions and success’s are all over the place.

Rear alignment amounts to adjusting the camber and that’s it. Adding or removing shims between the brake disc and inner drive shaft connection is how that’s accomplished. I read your post in the Series section and someone posted the front/rear alignment specs there. The front end aligns a little differently on these cars than modern American cars. Not better or worse, just different. If you don’t want to get neck deep in the science and procedures of alignment, finding a shop that has actual experience with the Jag setup would be important, I think.

You mention something about “ratcheting the car down” to do an alignment. Even in a parallel universe I can’t imagine what that is referring to. Again, as others have posted in the Series section, there are front/rear ride height setting tools that are specified in the Jaguar manual, easily made if you are handy. A copy of the Jaguar Shop Repair manual is a must if you intend to do any work yourself, which it sounds like your are, considering your engine swap.


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Hi Dave, that is super helpful. Thanks for all of the feedback. I’m going to replace the rear springs and shocks this weekend. I’ll let you know how it goes.

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i’m surprised to hear of your troubles getting a proper alignment. on my ls swap series 1, i used a series 3 front subframe and -30mm king springs all around.
took it to the shop, and i’d bet they did not have the special jag tools.
they set the alignment for what they called “good driveability” and said, if i didn’t like it or it pulls bring it back and they’ll change it.
been fine.
i may have the alignment sheet posted in my ls1 swap thread.

A few points:

  1. Rear coil overs. It is the springs that support the vehicle and in a measure control ride height the shocks are best termed as dampeners, and control the spring load and unload as the suspension reacts to the road conditions. Same in front although the architecture is different.

  2. Lower the front and the rear will rise.

  3. My car was a bit low up front when powered by the DOHC, I liked it that way, A neat rake…
    When I installed the LT1, the nose came up a tad. I measured it and it was now at factory ride heifht ! Still ok with me.

  4. I reshod my 83 with XJS 15" lattice wheels
    715 x 15 x 7, Just right. Fill the wells just right and clear at all angles…

5.Jjaguar alignment instructions include the use of special tools. The idea is to pull the suspension into a "base line ". their specs are at the base line… Some say it is a gotta be. others, not so much.

My car is an 83 XJ6. The Lt1 is such a neat option… It looks right at home. teh 4L60E transmission ratios fit right in with the rear ratio and the torque curve. .70 OD x 2.88 is tall. The SBC pulls it just fine… The donor car rear ratio was 3.09. Clo

Carlse. The Fleetwood Brougham a big car…

I changed the rear springs/shocks over the weekend which brought the back end up a few inches, which it needed. If I put a level under the rocker panel, the car sits completely level. Which I believe is a good thing. On the front tires, there are about 3 inches between the tire and fender. The back fender just barley sits over the tire. Is that normal?