After weeks of searching for an off-road project I am starting to think about a Classic Rangie instead of a Disco-1. I have found a 1991 3.9EFi with 100k on it which is in decent nick.

Be interested in any opinions: I think the classic would make a better off-road project - more interesting, and the ones I've seen are all in better nick body-wise than newer Disco-1s.

I have been told that the 3.9EFi is the most reliable of the V8 motors - any opinion on this? Does that age of V8 still suffer from porous blocks or liners?

I think this age of car has a limited slip diff and no diff-lock - does that make a major difference for offroading?

Cheers
Jock

Well apart from exterior sheet metal they are essentially the same vehicle so it boils down to looks and what you want to do with it. There are probably more disco 1s out there which means they are cheaper.

In my view the most reliable is a 3.5 carb but that's 'cos I don't understand electronics. There are many people on here who think efi is the mutts nuts but if you look at all the help threads for efi, the answer is always 'try this sensor or that sensor'.

As far as I am aware, all RRC have Hi & Low ratio and a diff lock.

Cheers

Chris

Ragtag said:

Well apart from exterior sheet metal they are essentially the same vehicle so it boils down to looks and what you want to do with it. There are probably more disco 1s out there which means they are cheaper.

In my view the most reliable is a 3.5 carb but that's 'cos I don't understand electronics. There are many people on here who think efi is the mutts nuts but if you look at all the help threads for efi, the answer is always 'try this sensor or that sensor'.

As far as I am aware, all RRC have Hi & Low ratio and a diff lock.

Cheers

Chris

Click to expand...

Ha Ha, this is a classic

Almost every Engineer will tell you that efi is 10 times more reliable than carbs in every way but a lot of mechanics of a certain era will tell you there's a lot less to go wrong with carbs. Its all about demographs.
Few young (<40) mechanics have the no how and experience to set up carbs correctly and so unless you or your mechanic are carb heads stay well away.
The 3.9 has the added advantage of extra power and torque over the 3.5 and efi is self adjusting for all atmospheric/elevation conditions.
Yes, it doesn't have the same reputation for slipped liners/porous block problems as the 4.6 but at over 120k you nee to be thinking about replacing the camshaft and chain. But view that as an oppotunity to release more torque via an uprated cam rather than thinking of it as a cost incurred.

Every RRC has a high and low box but I'm nearly sure that all RRC's after the face lift in 1986 had VC coupling centre diffs rather than lockable ones but it may have been a bit later. 1991 definitely had a VC coupling rather than a diff lock. No RRC's have any axle diff locks fitted as standard. Some 1994/95 Softdash models have pretty effective rear wheel Traction control as a diff-lock substitute.
Others may argue but I'm convinced that the VC is no disadvantage off-road. It offers significant advantages in traction while turning whereas its main drawback would be in something extreme like rock climbing where you need equal torque distribution. In most situations momentum is king and the added manoeuverability/traction the VC offers makes it marginally better than a locked up diff.
Either way it will be the guy/gal behind the wheel that will make the biggest difference on whether you get stuck or not.

I agree with Spud.

If you get a 3.9EFI you may have some running issues but when it's sorted it is really hard to fault. It took me 12 months to get my 3.9 to where it needed to be and I haven't looked back really. Maintenance is very important, stay on top of it.

As for diff lock, a '91 will have viscous coupling. I have found no problems in the gloop and sometimes I would have to say the combination of VC and auto box are actually an advantage. If you have an RRC with ABS, you can use the brakes to your advantage as well - they actually give you a lot of control where by rights you should be locked up and sliding out of control.

I love my Classic, it aint perfect but it is huge fun and it makes the right noise.

A classic is the way ahead , takes a bit to get them sorted !

fett said:

A classic is the way ahead , takes a bit to get them sorted !

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cant beat a classic.

Spud - thanks for the techie info - I think you are right about the carbs. Don't think they are ever used now because of the emissions rules and I haven't looked at any since I had a bike abt 5 years ago. You can **** around for hours trying to get them right.

This one does have VC so that explains the lack of diff lock, but doesn't sound like a problem. I have slid about in mud and up and down hills in my P38 with no diff lock (ETC right enough....)

Maintenance no probs - I can do all that crap myself.

I am thinking a 3" lift to start with, some decent gas shocks plus good set of steels and AT tyres.

Thanks for the comments - I'll let you know!

Jock

SpudH said:

Ha Ha, this is a classic

...... a lot of mechanics of a certain era will tell you there's a lot less to go wrong with carbs. Its all about demographs.
Few young (<40) mechanics have the no how and experience to set up carbs correctly

Every RRC has a high and low box but I'm nearly sure that all RRC's after the face lift in 1986 had VC coupling centre diffs rather than lockable ones but it may have been a bit later. 1991 definitely had a VC coupling rather than a diff lock. No RRC's have any axle diff locks fitted as standard. Some 1994/95 Softdash models have pretty effective rear wheel Traction control as a diff-lock substitute.

Click to expand...

What can I tell you.......I'm 53

As it happens, I have a 3.9 EFI (1994) lump waiting to drop into my old truck so I'll have all the EFI bits going spare once I have swapped the carbs over

Interesting about the VC, I thought that came in with the P38. I'll have to read up on how that works as I assume my '94 Disco donor would have had this system as well.

Thanks for the info.

Cheers

Chris

Sorry to sound stupid here, but with a VC and no diff-lock, and no ETC obviously, what happens if a wheel gets stranded? Won't it just spin round?

SpudH said:

Ha Ha, this is a classic


Yes, it doesn't have the same reputation for slipped liners/porous block problems as the 4.6 but at over 120k you nee to be thinking about replacing the camshaft and chain. But view that as an oppotunity to release more torque via an uprated cam rather than thinking of it as a cost incurred.

Click to expand...

May not be as infamous as the 4.6 for slipped liners but can I assure folks that (as a 94mm bore block) 3.9's can & do - I speak from personal bitter experience & before you ask, no it wasn't cooked first or even driven hard. My erstwhile mate had the same problem with his the following year, his was a '91 & mine '93.

Ive kept a 1992 RRC brochure from my cub collectors badge I love them so much

Wanted a RRC 3.9 LPG but couldnt find the right one at the time

Happy with the disco LPG as the disco fits more in

BigJock2005 said:

Sorry to sound stupid here, but with a VC and no diff-lock, and no ETC obviously, what happens if a wheel gets stranded? Won't it just spin round?

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Off that - just caught the thread below which answered my question!