Rover V8 Gearbox And Rear Axle

[Guest Stuartl]

After dropping the b*****k of buying a 4WD Range Rover Gearbox with my V8 Engine I am now looking at getting an SD1 gearbox. The question is do I stick with the one that was originally fitted to a 3500 SD1 or would an alternative ratio be more suited to the lighter car?

 

Also I am after ideas for a suitable rear axle/diff that wont implode under the V8 power.

 

As always, suggestions are very gratefully accepted!

 

Thanks

 

Stuart

[Guest Tim Norman]

I'm running 225/50/15 tyres with a rover box and a 3.62 diff. That gives me 70mph at 3000 rpm. The torque the engine gives means I can forget about 1st if I want. It all depends what you want to use the car for. I did have some 17" rims and I could cruise at 70 at 2500rpm but it made the gearing a bit too tall for what I wanted.

 

Because

[Guest Tim Norman]

I'm running 225/50/15 tyres with a rover box and a 3.62 diff. That gives me 70mph at 3000 rpm. The torque the engine gives means I can forget about 1st if I want. It all depends what you want to use the car for. I did have some 17" rims and I could cruise at 70 at 2500rpm but it made the gearing a bit too tall for what I wanted.

 

Because the car is light you are more likely to spin the wheels rather than destroy the diff. That said I would still make sure I had the strogest diff I could.

[Swan Jnr]

i got exactly the same advice re 1st gear. with a four speed all you'll do is spin the wheels in it.

sd1 box is a good match for me. easy cruising when you want it, and glorious noise when you push it a bit.

hearing what you say about 3000rpm at 70 mph tim, i either have a different diff, or my electonic rev counter is about a thousand mph too low!

[Guest Stuartl]

i got exactly the same advice re 1st gear. with a four speed all you'll do is spin the wheels in it.

sd1 box is a good match for me. easy cruising when you want it, and glorious noise when you push it a bit.

hearing what you say about 3000rpm at 70 mph tim, i either have a different diff, or my electonic rev counter is about a thousand mph too low!

 

All interesting stuff!! What rear axles/diffs are you guys using?

[Guest Tim Norman]

I had my doubts about the revs but I checked it against a spread sheet I have that calculates the speed for a given tyre size, diff ratio, gear ratios. email me and I'll send it to you. IIRC it came from someone on here many moons ago

[Guest Stuartl]

>>>>>>>>>Because the car is light you are more likely to spin the wheels rather than destroy the diff. That said I would still make sure I had the strongest diff I could.

 

Do you think I would wreck the Sierra Diff and axle or would it survive normal road use?

[Guest Tim Norman]

The normal sierra diff would survive. Just don't over tyre it. I have 225/50/15 and can't get any heat in to the tyres I have a few more ideas to try before I go back to the 195/50/15 which I know got warm. It may be I just wasn't driving hard enough!!

[Swan Jnr]

funny you should ention the diff. mines just started whining after a track day at curborough last wednesday.

praying its run low on oil (it has always leaked from the filler!)

 

i'm sure tim drives his a lot harder than i do mine (he has lots more power too) and if his is ok a sierra diff should be fine.

 

tim i'll email you....

 

paul

[Guest Stuartl]

Great, hopefully all the rear axle will needwill be a blast off and a coat of nice POR-15 then .

 

Then I will have so get the propshaft made to suit

[Guest salty_monk]

Paul if it has run low on oil & started whining it probably means burnt teeth & it will whine forever. I had that issue with one I had.

 

They can usually go on for a long time even when noisy.

 

Dan

[Swan Jnr]

Paul if it has run low on oil & started whining it probably means burnt teeth & it will whine forever.

 

B*M

 

oh well just have to rev it harder to drown out the noise!

[Guest Stuartl]

B*M

 

oh well just have to rev it harder to drown out the noise!

 

 

My old Sylva Striker diff started to whine and like a fool I ignored it until one day at thankfully low speed it tied itself in knots!