The reason for the recent sagging (apparently) is that when MMC changed from six leaves to four, the spec wasn't good enough and a different supplier was sourced in '2012'. I say this because Mulfab were surprised that Bumble was sagging, and think that he may be one of the last with the weak springs. It was our Scotland tour that really brought this to my attention.
Anyway, a few stats:
Almost all the fasteners are 5/8"AF.
The seat belt nuts are 16mm, the bolts are 17mm.
Here are a few unscientific measurements:
New spring measurement of unloaded camber - 15cm
Old spring measurement of unloaded camber - 12.2cm
From lower plate to chassis - (bigger measurement = lower ride height).
Old springs - N/S 6.5cm, O/S 7.3cm.
New springs - N/S 2.6cm, O/S 3.0cm.
Gain in height ...3.9cm, ... 4.3cm.
Clearance to body where contact took place - old spring 2.8cm, new spring 4.8cm.
To underside of running board at rear (just in front of rear wheel):
Old springs: N/S 21.0cm, O/S 20.4cm
New springs: N/S 23.8cm, O/S 23.8cm
Gain .............2.8cm, ... 3.4cm
Next will be a road test. Pressures set to 24psi.
If I were a Boy Scout I would now be sewing on my Leaf Spring badge, next to my Kingpin badge, and Creative Use of Neoprene badge.
