Is anyone a transmission expert that can give advice?

Hi
I am embarking on a ground up rebuild of a Ex-MoD 110 V8
For a number of reasons I'm keen to use an auto box and have a newish ZF 4HP 22
I am also looking to use rear discs because of an increased BHP output (target 250-300 ish)

So I have acquired an ex-Wolf rear Salisbury with discs, and hoping to secure this ZF box.
What I don't understand enough about is how I get the right ratios end to end?

I get the theory at a high level - e.g. Engine turns at 3000 rpm ratios applied wheels turn at xxxxrpm rolling radius is yyy cm for 285/16 tyres therefore in 1st gear speed will be zz mph at 3000 rpm

What I don't get is if the bits I have are correct to bolt together and produce that combo - for example I don't know what ratio the Salisbury diff is and I don't know what the ratios are in the ZF/transfer box

Also assuming the bits are ok I want to get the axle refurbished but can't find someone that is a Salisbury diff expert (seen JamesMartin mentioned ) so need to check it is ok ratio wise before I start
I'd like to do the Salisbury rebuild myself but think it's too complicated and I don't have the tools

I also don't get how I make the box work in terms of telling it to change gear/kick down and even which gear selectors I can use (I'd love something electronic like a RR Sport/Disco rather than a gear lever like a RR classic)

• So is there a simple test I can do on the axle to check axle ratio
• Who can refurb Salisbury
• What are the right ratios (and how can I get the right ones like by serial number of transfer box)
• What about the control of the auto box
• Anyone live near Hitchin that needs a project to help on

Thanks
CC

salisbury will either 4.7 or more likely 3.54,they are the only 2 ratios used on landies,if you turn the diff flange and both hubs turn it would take 3.54 or 4.7 turns to get hubs to turn once,if you lock one hub,the other hub will turn twice as fast so to get that hub to turn once youd need to turn diff flange 1.75s bal tool for 3.54 ratio and 2.35 for 4.7 ratio,the only special tools needed are god pullers to remove the bearings from the carrier and inner most pinion bearing and a dti for measuring
presumably your going high compression rather than the std low compression used
if you used disco or rr sized tyres a 1.22 t box and the salisbury would give same operation as disco or rrc,though most want bigger tyres on defenders

jamesmartin said:

salisbury will either 4.7 or more likely 3.54,they are the only 2 ratios used on landies,if you turn the diff flange and both hubs turn it would take 3.54 or 4.7 turns to get hubs to turn once,if you lock one hub,the other hub will turn twice as fast so to get that hub to turn once youd need to turn diff flange 1.75s bal tool for 3.54 ratio and 2.35 for 4.7 ratio,the only special tools needed are god pullers to remove the bearings from the carrier and inner most pinion bearing and a dti for measuring
presumably your going high compression rather than the std low compression used
if you used disco or rr sized tyres a 1.22 t box and the salisbury would give same operation as disco or rrc,though most want bigger tyres on defenders

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Firstly jamesmartin thanks for the feedback. Exactly what I was after!

Really haven't decided to stretch the current 3.5V8 or go for a 3.9 or 4.0 maybe 4.6 but the double bolted crank appeals if the loss of dizzy and conversation to electronic ignition is a pain. I think I'll get the block pressure tested and maybe tophatted if OK, then build up the 3.5 for optimum power and reliability - I really don't like hard shoulders!

Tyres - initially I was looking at civvie Defender tyres (Like AT Grabbers) and yes probably looking to keep them big(ish) for clearance but you raise a good point maybe going a bit more alloy 20 inch low profile would be more in keeping with the style I'm looking for - more Kahn than farmer Giles!!!

Jamesmartin do you do Salisbury rebuilding? I really want to check it's not going to disintegrate in 10k miles and/or it hasn't got teeth missing etc. So is there a sensible way to open the diff and remove the half shafts and inspect it to see if it needs bearings seals etc.? If not put it back together - if it is scruffy replace the bits that need it.

CC

yes i rebuild them,few of us do it seems now,you could remove rear cover and get an idea of condition,but it needs stripping to be 100% on condition
any 3.9 or bigger id top hat liner 3.5 obviously doesnt need it

jamesmartin said:

yes i rebuild them,few of us do it seems now,you could remove rear cover and get an idea of condition,but it needs stripping to be 100% on condition
any 3.9 or bigger id top hat liner 3.5 obviously doesnt need it

Click to expand...

Thanks

Jamesmartin would you like to pm me with estimated costs please?

CC

You say you have an ex Wolf Salisbury? Thought the Wolf 110 used a braced rover axle? Know the 110 and tithonus used Salisbury but thought it was changed for the Wolf. As for tyres I run 235/85 cooper discoverers on my Tithonus, bit of noise on road but really good on the lanes.