Thread: wheel ratio

The ratios cant be changed without a box swap however the shifting points can be adjusted and if you drive it the same way long enough it will adjust them something like 10% of the nominal values as a "learning" thing.

generally if you go about 10% higher in the wheel size putting it in sports generally makes it go like it used to but you pay for it at the tank.


Changing the Tcase ratio for a deefer set works kind of but can be a step too far.

Land Rover gear ratios

has a fairly good ready reckoner of the ratios.

Originally Posted by Slunnie

I just put it in sports mode and thats a pretty big improvement for a mapped and intercooled Td5. Far more drivable and no charge.

I've settled on that, too with a stock engine.

Lockup in third around town at 60, and I just leave it in locked up 3rd up to 80 now.
It holds lockup 4th with CC engaged on the hills in Sport mode, too, whereas it'll kickback a little too readily at 110km/h without cruise engaged.
Even left in drive it uses lockup 2nd and 3rd on the narrow, twisty, hilly roads around here quite nicely.

Originally Posted by trout1105

I seriously wouldnt bother with messing about with the programming or altering the TC ratios, You will soon get jaded with the excess fuel usage and the lack of torque with the oversize tyres ( even though they may look "Cool") and revert back to a reasonable tyre size so that you can take full advantage of you D2's inherant 4WD capabillity in stock form

+1 for that ^^^

Originally Posted by rick130

The TD5, even in stockish form goes pretty damned well with 31's and 32's, which are really pretty mild in this day and age.
Mines only had an EGR delete and a 3" pipe (in prep for more mods) and the torque is better than stock, even with the taller tyres.
Fuel consumption is better, too.

And what EGTs do you get?... i fitted 5.4% bigger than standard tyres and the EGT increased with 100*C just for that... and the breaking distance is affected as well together with all the other active ABS functions as the VSS is altered

Fueling hasn't increased so I haven't bothered fitting a pyro, and having experience with big exhausts on other diesels they drop egt's anyway.
With a 300Tdi I had something like a 25° drop in peak EGT's with just the larger bore exhaust on my test mountain pass.

Braking is better than stock, the new Falken AT's have more grip on bitumen than the 255/55 Pirelli Verde's, (or 235/75 GT Radials fitted prior) and with slotted rotors, SS braided hoses and custom race compound pads with an extremely high Mu (coefficient of friction) and properly bled system it stops far better than a stock vehicle.
The car easily passes the brake testing requirements we have here for yearly registration testing.
I compared this years results to last, the same driver and machine was used and average and highest G attained is much greater with much lower pedal pressure after fitting upgraded brakes and larger tyres.


A stock car is a compromise, and not all of us are happy with those compromises.
With considered modifications you can actually make it better and barely lose and sometimes gain all round.

I have owned a 4WD of various makes/models for the past 40 years and I too have experimented with oversize tyres, lifts and various engine/exhaust mods But at the end of the day as long as you have fitted a decent set of Off Road tyres to the vehicle Most 4WD's will perform well in stock form.
YES a better set of aftermarket brakes is always an improvement over a stock set of brakes But I am not a fan of oversize tyres/wheels because every time I have tried this I have lost torque and fuel economy and the Only gain was a small amount of extra clearance.
Then you have the extra strain on the drivetrain and brakes also with any lift (this includes oversize tyres) you will loose some stability and it effects the driveability as well.

I have NO lift, No engine or exhaust mods on my D2a V8 and the Only thing that isn't stock on the old girl is the set of DBA slotted rotors and heavy duty pads otherwise the car is completely "Stock".
The tyres are 245/70/16 Mickey Thompson ATZ p3's which are certainly not "Monster Tyres" and yet I have absolutely NO problems traversing any type of terrain that I choose to.

The D2 is a VERY capable 4wd without having to go overboard on tyres and other mods

Originally Posted by rick130

it'll kickback a little too readily at 110km/h

Remap will sort that

Originally Posted by sierrafery

And what EGTs do you get?... i fitted 5.4% bigger than standard tyres and the EGT increased with 100*C just for that... and the breaking distance is affected as well together with all the other active ABS functions as the VSS is altered

Did you account for speedo error ?, if you did , your revs would be lower for the same speed , if you didn't your speed would be 5.4% higher , either way , if you take that in to account you might find the 100* difference would diminish.
I have remapped many td5's but not without mods to breathing and brakes first , most of which had bigger tyres, which aren't just for looks around here ( lots of ruts , rocks , steep sand climbs etc ) which is helpful with clearance under the diffs.
5-6 % with a remap is actually a very good combination with the standard T case ratio , as the car is just that bit more relaxed on the highway.
With my own heavily modded Td5 , it takes from 0-160 ( tested on airstrip ) before EGT will hit 770.
After all these years and all these td5's not blowing up I would have thought it well established that they are an extremely tough unit.....unlike the later diesels.
Ashcroft do a 1.3 ratio but not in the Q gears , for those going to 10% bigger, or 3.7 diffs

Originally Posted by rick130

Fueling hasn't increased so I haven't bothered fitting a pyro, and having experience with big exhausts on other diesels they drop egt's anyway.
With a 300Tdi I had something like a 25° drop in peak EGT's with just the larger bore exhaust on my test mountain pass.

Braking is better than stock, the new Falken AT's have more grip on bitumen than the 255/55 Pirelli Verde's, (or 235/75 GT Radials fitted prior) and with slotted rotors, SS braided hoses and custom race compound pads with an extremely high Mu (coefficient of friction) and properly bled system it stops far better than a stock vehicle.
The car easily passes the brake testing requirements we have here for yearly registration testing.
I compared this years results to last, the same driver and machine was used and average and highest G attained is much greater with much lower pedal pressure after fitting upgraded brakes and larger tyres.


A stock car is a compromise, and not all of us are happy with those compromises.
With considered modifications you can actually make it better and barely lose and sometimes gain all round.

Yep, that happy with mine , the (modded) RRS I have, just sits around most of the time.I have more fun in the D2.
Will you be be getting a pyro and remap? , they are able to get high EGT under the right conditions stock, but not enough to kill 'em

Originally Posted by scarry

Or just borrow a GPS such as a Garmin street finder,if you don't have one.

It will let you know what your actual speed is,and they are very accurate.

.... or consider a HUD speedometer. I purchased one after I upgraded to larger tyres and used it until I installed a speedo correction unit from HUNTER Di SPARES.

Originally Posted by Slunnie

I just put it in sports mode and thats a pretty big improvement for a mapped and intercooled Td5. Far more drivable and no charge.

I find the sports mode shift points better suited for normal driving, unfortunately sports mode resets to 'normal' each time the engine is turned off. Is it possible to set sports mode as the default ?

Deano