I've been down this path. I had a set of +50mm spacers fitted a few months ago. Difference is I also had a set of +50mm shocks fitted at the same time. I found the front was bottoming out the shocks on compression on the front, and also on the rear unless I put about 8 psi in the Polyairs.
From what I can work out, the front with the spacer and stock length shocks and coils should work, only issue is there will be no increase in overall wheel travel that longer shocks offer. If the coils you have are +50mm longer that's 100mm over all, I think you will have all sorts of dramas with driveline angles and axle centering requiring adjustable panhard rods. That's why I only had the spacers installed and left the stock soft coils fitted. Every other 4WD I have lifted over the years using longer springs ended up with the ride being quite harsh, by using the spacers and stock coils I still get my extra 50mm and maintain the soft cushy ride.
I've just ordered a set of +50mm shock turret spacers that will be fitted by my mechanic later this week to solve the bottoming issues.
I'm sure others with their own experiences will offer their input. Just my 2 cents
Cheers William
'98 Discovery Tdi SE7 *SOLD*
'05 BMW R1150 GS Adventure
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