Inches to fully release front spring

1989 XJ6 XJ40 3.6L
Front Suspension
With car jacked up in front…front suspension and wheels off the ground, fully extended, hanging down and A arms at lowest position stopped by max. extension of shock absorber. What length of threaded rods or long bolt… to replace original bolts on lower front spring pan would allow the spring to be fully extended? 3 4 5 more?? inches?? Or If one lowered the lower spring pan with wheels and suspension --fully extended—as mentioned above how many inches lowering the “pan” before spring has no more compression?

and where in heck is a simple POST QUESTION button… hmmm
do i press “create topic” or “saved” ? not very clear

Use a spring compressor such as this;-

Up,loading…
Much safer, the spring is under a large amount of pressure and it is in a curved setting.
The threaded rod is 3/4” 19mm the bolt at the end should be a 1/4’ spring dowel and the angle piece is on the rod the wrong way, it should be the other way around.

For the earlier saloons the guide screws are 8" long. The XJ40 probably isn’t that far off.

Be careful, there’s a huge amount of energy stored in those springs.

In the category (XJ40 in this case) click on “New topic” to start a new topic. The composer will open. Once you’re done click on “Reply” to submit your question.

on an XJ6, 1metre of rod cut into 3 lengths is sufficient + nuts & washers.

I use this method in preference to the correct Jaguar Factory Tool