'95 Disco Gearing options... Transmission, T-Case, Diffs? Anyone experienced?

[Orange Disco]

Hey Guys,

I've a '95 Disco, 3.9L that I would like to mod a bit to improve its off road capabilities. Bottom line, I'll swap the suspension first. I was gonna inquire about perhaps tuning the rover engine a bit, if worth it. But I'm under the impression that gearing would probably have the most dramatic effect on the vehicle performance off road. Anyone familiar wide any successful diffs, transmission, T-Case mods? I'm just working on a game plan here.

I'll start some online research, but I thought I'd ask the club guys.

Thanx!

[Red90]

Stock gearing should be fine unless you are going with huge tires. It is much lower than most vehicles. Normally changing the timing chain and sprockets adds a bunch of power.

On a Disco more important things to add are armour as the body is prone to damage.

My order of changes.

- tow points
- armour including bumpers.
- better tires.
- winch
- better diffs, stronger half shafts and CV joints.
- more flexible suspension.

[Trevor]

John list is a good one, the only thing I might bump up the list is a 2" OME spring lift with shocks, so you can fit 265/75R16 tires. 31.5" tires are about as small as you want to run if you're spending much time in the Alberta skeg-lands.

Gearing changes really aren't worth it unless you're planning on getting into serious rock crawling. The stock LT230 T-case is very good with a very good low gear ratio. There are lots of better things to direct you funds towards.

I don't have any experience driving the 3.9 so I can't offer any insight there. 

[Red90]

265 on a Disco 1 requires a lot of changes to fit properly. 245/75 is much easier with only small changes. Personally I don't see tire size as that important.

[Red90]

For off road ability improvement, the things that will make the biggest impact, IMO, are tires with good traction and rear locking differential.

[Trevor]

265 on a Disco 1 requires a lot of changes to fit properly. 245/75 is much easier with only small changes. Personally I don't see tire size as that important.

Really? Aren't the 7.5R16's they used to outfit the Camel trucks about 31" in size? Or do I have my sizes mixed up?

[Red90]

The CT trucks used 7.00x16, which is fairly easy to fit (30.5" x 8").  It is petty much the same size as a 215/85R16.  Usually a 10 second trim is all that is needed.  In fact, everyone used to always call it "the Camel cut".  The 245/75R16 (30.5" x 9.6") is a wider option that fits as well with only a small and easy trim.

Stock tires are 29" x 8" or 9".

7.50x16 (31.7" x 8.3") are easier to fit than 265/75R16 (31.6" x 10.4").  The taller tires "need" longer bump stops to prevent the tire bottoming out and that then means you "should" relocate shocks, add spring retainers and longer brake lines in order to get travel back.  They also require more trimming and they don't fit on the spare tire mount as they hit the bumper.  The wider tires get into more and more trimming.  That all said, a lot of people tend not to notice...  They fit lift springs and the heavy springs make it difficult to compress to the bump stops.  All of the interference happens at maximum articulation.  Personally, I like to ensure that the tires clear under all conditions. So I always take the springs out and test the full range of axle travel.  In addition to the tire clearance issue it exposes a lot of possible problems like shocks bottoming or other suspension components running out of travel.

[Matt H]

As far as engine performance go's start with cleaning out any gunk build up and improving the ign spark. Rover V8's, especially older distributor models, need a good strong spark to run properly. Use the expensive gas. They are designed to run on the much higher octane European gas. Everything else is just the same as any other pushrod V8 you ever worked on.

I like a 235/85r16 on stock alloys on a Disco.

My 2c

[Orange Disco]

Thanx for all the replies. I got the vehicle running, but it needs a bit of tune up. We are suspecting a IACV sensor sticking up here and there,but otherwise this engine only has 155k on it and tested well above 150's on comp test and all, so, I'm really happy. A little TLC...

Anyone as recommendation on lift/ dislocation kits? Not OME, it's just me, I'm just not a fan. TF maybe? I was looking to get a TF235 - 5 inch Extreme Dislocation Kit. Please, redirect me if there is already a post on that topic.

I decided to run 255/85r16 for tire, probably TOYO Open country M/T, I had nothing but great results with those in years.

John is right, I'll armour the b*tch! I'll start with some HD steering rods and plates all under.

I'll run the engine stock for a while, then plan the next move. But John got me interested in the sprockets/ T-chain mod.

[Matt H]

You don't need a 5" dislocating extreme lift to run a narrow 33" tire.

TF or OME? You pay's your money you takes your choice. I run a very old set of OME coils on my Rangie.

Honestly, anything more than a 2" suspension lift and you will create more problems than you solve. I've tried it and it just doesn't work as well as stock. Most "kits" are designed to gain height for tire clearance at the expense of suspension travel. 

Dislocating the rear springs is a bit of a contentious subject in Land Rover circles. Personally I don't think it helps very much but you will find others that rave about how great it is.

Red90 has an excellent web page on springs, spring rates and what tire fits what with how much work.

My2c

[Orange Disco]

Sounds good, where is the link to this page?

[Orange Disco]

How about the 3" kit? Seems like a better option, doesn't it? That way a guy could fit 33" properly on there. You could lift the body 2" with that... What do you think?

[Red90]

http://www.red90.ca/rovers/

255/85R16 requires a fair bit of work to fit properly.  Nobody makes proper "kits" that cover everything you require, IMO.  You need to figure it out and put together your own group of parts depending on what you want as an end result.