Hello, I have a 1986 90" with a freshly machine-shop refurbished 200tdi mated to a decent LT77. I will not be off-roading or towing 3 ton loads but want better road speed. Should I fit a Disco1 transfer box?
Tbh the 1.4 is pretty good at what it does in the 90/110 models, I found the 1.2 was to highly geared and the box effectively became a 4 speed as 5th was unusable a lot of the time, it was okay on fast a roads and motorways, but then it lacked grunt on long inclines, this was all solo running empty.
So in my humble opinion if them tyres in your pic are 235/85 then stick with the 1.4.
A lot depends on the terrain around you and your regular haunts.
I have a 110, 200tdi with the disco box, on 235/80s.
I tow and move up to 1 ton of boat and trailer, up to 25 miles in Norfolk no problem.
I drive up to 200 miles in a single trip, not towing, half "A " road, half A1/A1M, I find the disco box much better, quieter, for comparatively high speed 60-70mph driving. I don't mind dropping to 4th occasionally it's not that. different to being in the old 5th.