Old Leafsprung Land Rovers

I could do with higher gearing now. Am i right in thinking:


I can fit an overdrive at a massively inflated sill price which will possibly be ****. I also have a rear pto for the compressor so id like to keep that.

I can put higher ratio diffs in but its not as easy in a 109 rear axle plus il lose the useful 1st low for crawling.

I can fit bigger tyres.9.00s would be awesome but how much more will they give me? plus i dont want to pay 175 odd quid a corner!

If you want higher gearing for speed, forget the 900s, as they're low rated as standard.

Depends what breed of 9.00 you have - some of the bar grips are only speed rated for 80mph, but I'd be fairly sure that the XZLs that are available new (at serious cash) would have a higher rating...

It's all a bit academic, as none of the tyres in question are rated so low that you would be likely to exceed said speed in normal use...

Well, as you've already put the kybosh on the three common options in your first post, the only other option (if you can't find Rover P4 diffs - did they do a Salisbury rear?) is an Ashcroft high ratio box.

Expensive, but cheaper than a new overdrive, I think, and you keep the low ratio the same, it's just the high ratios which change.

Of course, it depends on your engine as well - 200TDi pulls 3.54 diffs easily, and low first is still a reasonable crawler gear (have you seen our youtube vid of three heavy Carawagons climbing Rudland Rigg - all 200TDi with 3.54 diffs and 7.50 tyres   ).

Considering the standard petrol and diesel engines. What options exist for gearing up that the engine will cope with?

Probably overdrive is the best option for standard engines.
You can choose to 'gear up' whenever you want then, rather than being stuck with permanent over-gearing.

Also handy for splitting 3rd/4th gear when 3rd is a little low and 4th a little high   

New overdrives are available if you have the money (around £1200+  )  if you don't want to take a risk on a s/h one.

Use a 2a 109 rear axle for the Rover diff....