Diffs - difflocks, atb or lsd

Hi all.

I've gone and done it - bought a 90.
It's a project that needs a new chassis - so I'll be putting my 4.6 v8 in it.
I have a lovely sparkly Richards chassis, and will shortly start building it up.

I'll be rebuilding every bit that I fit - first up are the axles.

What's the best to fit regarding the diffs?

The engine will have about 250 bhp.
I won't be doing rediculous off roading in it, but will be towing, often on muddy fields etc.

To date, I've not had any problems with grip with this engine in my RRC, but since I'll probably be getting the diffs rebuilt, I thought I'd think about upgrading the diffs.

I was thinking of the Ashcroft ATB diff - any drawbacks on this bit of kit?
What are the experiences out there?
I've heard that it can give a bit of an odd driving dynamic - is this true?



Any advice would be great, thanks,
Mike.

I'd probably go with a detroit locker in the rear and trutrac or Ashcroft ATB in the front or else atbs all round.

air lockers far more useful offroad as you can have the diffs open or locked depending on the situation or obstacles your trying to get around but on the road and towing in muddy fields, the detroit or atbs would be easier and less work... also much cheaper of course as they are a much cheaper diff and no extras like compressors, air-lines, solenoids etc.

ATBs all round are probably the least obtrusive under normal conditions. dissadvantage of them however is one wheel has to start spinning in order for the diff center to lock up so you kinda have to get half stuck before they start helping you out and second problem of them is if you get cross-axled and there's no load at all on the spinning wheel so it won't transfer any torque to the wheel that has grip (Can fool it by left foot braking however)

Only drawback of a detroit locker in the rear is if your on grassy side-slopes, it can be abit tricky as you might end up facing the wrong way easily if your not careful. Definitely not a nice situation to be if you've a trailer attached!
It can have it's disadvantages offroading too but the pros probably outweigh the cons unless your really getting into it seriously to warrent air lockers

At the price, the ashcroft atb's look good.
Also, I like the idea that they are always working.

I've never actually needed lockers etc on my RRC, even in the stickiest of situations, the car has performed really well ( and no traction control - just a steady right foot) , so I'm reluctant to go for the cost and complexity of lockers.

I was confusing the atb's for "unlockers" which my mate tried and didn't get on with.

Thanks for the advice.

Mike.

"unlockers" as in ones like the Detroit locker?

In what way did he not get on well with them? He didn't try fitting one to the front did he?

you dont really want a detroit in the rear of a 90 as there only meant to be fitted in wheelbases of 130" and above, even though people fit them in 110's, me included,
there have been a lot of failures in the rover axled 90's which to my mind is because the turning circle is to tight for them to unlock when cornering on hard surfaces,
no problems with the trutrac type though

It was on a 90 as it happens. He was happy enough, but felt that his wife would be put off by it.