I though I'd create a separate thread with the technique that I used to to lower (3/4") the front of my car (1989 XJS):

I added two 1/4" pieces of steel flat bar, bent at an angle to follow the A-arm contour on each side of A-arm. This amounted to a thickness of ~13 mm.


I used a threaded rod through the center of the spring to hold the spring pan in place while I replaced each original bolt with a a longer replacement bolt. I bought 1 1/2" bolts (3/8" 24 unf) but they were a tad long and needed to cut down a couple of threads to keep from bottoming out. Ideally you'd find 1 3/8" bolts (if they exist). (Ignore extra washers in pic below-this was before I shortened bolt)



Here they are installed:


Stock driver fender measured 28" from ground to fender through centerline of tire:




Lowered 3/4":



And here is end result:

 

Good work.


Cheers
DD

 

Lovely job. Maybe a spot of weld between the spacer and the spring pan to finish it off? Just a couple of beads to ensure the plate cannot jiggle out? Incidentally, the Allan Scott book on the racing TWR XJS says the lower the air dam to the road the more that front end lift is reduced, so lowering does not only make it look better, it makes it handle better at speed too.
Greg

 

don't see why I just could not use SS-steel washers... there is a gap already... the bar stock just seems... well I don't know...


yes it would be more open... and any water would just flow out and not be trapped... I live where there is no road salt... snow excetra... just rain now and again...

 

Using only washers would leave the bolts unsupported and subject to breakage, IMHO

Cheers
DD

 

I tend to agree with Doug. I think it would be a safer idea to weld onto the spring pan about a one inch wide spacer piece with a carefully sized drilled hole for the bolt, so the bolt was not loose in the hole. Also, when I redid mine (as standard) I bought high tensile bolts for a bit more peace of mind, although this is not necessary at all.
Greg

 

Or you could just $UP and save up for the higher rate lowered spring set...
I did all those on my Sprite and the best solution was the lowered racing springs...

for the rear they sell shocks with a threaded spring seats that is used to set the rear end height.... 4 required...
what height is it supposed to be? I think my conv. is too low....

 

I considered this but I couldn't find a definitive answer as to whether they actually lowered the car (XJS). Or maybe I'm mixing up threads with stock springs being too high.

 

.

must be me ,front still looks to high?

 

Ron, I think it will settle a great deal once in use. I think Andy will find he has lowered it quite a bit once it starts being used. I still think Andy, that your spacers should be welded to the spring pan though! After all, as we all know, what can go wrong, will go wrong, and having one pop out at the wrong time would be pretty bad!


On another topic from Jonathan, I think Andy has done the right thing to lower the car but not stiffen the springs. It is very hard to keep a decent ride quality on shortened springs.
Greg

 

The Jag found my stash.

 

This method of lowering the car was once pretty common on cars that had a the spring seat cup on the bottom. usually the spacers were even thicker. I think this is a good way to lower the car a bit without making the ride too harsh. I would just keep an eye on the rubber suspension stops. I would imagine the car might bottom out more often than normal.

 

There are also spacers under the spring. I removed these, which left my car about stock ride height after removing about 15kg from the front.

 

Hi I have just purchased a set of low front springs, they claim to have a 30mm lower ride height. As Rivguy mentioned I'm worried about the bump stops being to close now. Has anyone had any experience with this? Can you get shorter lower bump stops, or should I trim the Stock ones?

Cheers.

 

hi if you can find the front and rear springs from a mid to late 1985 -1989 XJS 3.6 sport these are a lot stiffer and a little lower than standard. I used these in my race car back in 203.I also used 10mil spacers made for each bolt this way they can not slip out.I also found because of the suspention geometry 10mil spacer actuatley lowered the car about 18mils cheers Ray.

 

This is a very timely thread. I’m interested in lowering the front of my 1986 XJ-S V-12 Car I recently bought.
Can I ask why the holes are slotted? I understand you used the center bolt with a piece of all thread to hold the spring in place so the center hole may have to be slotted. But couldn’t the forward and aft holes be not slotted and just remove one at a time, install the longer bolt and then the next?

also did this effect your alignment?

 

I don't know if it affected alignment because I did not have the car drivable before I lowered it. IE, I rebuilt the suspension and only "lot-drove" it before lowering.

I think I slotted them in order to keep as many bolts in as possible (during install) to ensure that the spring pan stayed aligned. You could simply have holes (not slots) and see if you can get the bolts started. I recall it being kinda tricky because of the fine threads and weird angle that the spring pan bolts enter the lower control arm.

The suspension did settle some more and the stance is perfect. Ride stayed nice too.

 

Lowering a car will affect alignment settings. Even with double wishbone camber does not stay constant through the full bump and rebound, toe will also be affected to some extent.

Anytime the suspension is changed it's a good idea to check alignment. I have 245 50 16's on the front and I have had to play with alignment settings to reduce tramlining. With the 215 65 15's I ran Zero toe I have had to increase toe in with the wide tyres to reduce wandering.