Freelander 1 Measuring yer wheel fred

blue beasty said:

Insulting me doesn't really support your view that you're not trolling

Once again this thread is a request for data. If you can't do anything other than pour scorn on the request than please leave the thread alone.

It's a simple request and I've asked politely.

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If a statement of fact is an insult then so be it, we will then wait and see what technical breakthrough it brings. But i do seriously doubt that will happen.

Man this is getting tiresome.
Anyone who doesn't want to join in this thread's train of thought doesn't have to.
Research is valid even if it proves that something postulated is NOT the case.
@Hippo will get figures and will either be able to make a proposition (which can be analysed when there is something to analyse) or find that his idea is wrong and he can explain what and why.
This thread isn't compulsory. Those who can't be arsed or think @Hippo is timewasting can ignore it.

I have to admit I missed the point of this thread the first time I looked at it but will now try to get some figures for my 1.8. They may be different from the TD4's and V6's due to the weight difference of the engine. As for the Trolling going on here a certain poster will be my choice of 'Arsehole of the week'
A wonderful and well deserved recognition for all his hard work to achieve such recognition, and I see he is in the lead too. Well done that man

B34R said:

I beg to differ
100kg = 1000N give or take, at 1.2 meters that's 1200NM of torque
The K series engine outputs 165NM of torque into the gearbox, which is x3.25 in first gear = 536 NM
The IRD is a ratio of about 1.4 iirc? = 750NM Torque to the wheels.

A 100kg bloke stood on a 1.2 meter bar will accelerate the car 1.6 times faster than the K series flat out

Sad I know.

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Sorry B34R but you missed the final drive ratio off your equation.
K series torque of 165Nm
X
First gear reduction 3.25
X
Final drive ratio of 4.2
X
IRD reduction of 1.4
Gives 3153.15Nm of torque at the front wheel hub. The output to the rear is geared up by 3.198 iirc
This gives 985.97 Nm or torque at the IRD pinion. The rear diff ratio of 3.2 multiplies the torque back up to a more sensible amount, under the control of the VCU.
The hub torque of the V6 is considerably more.
V6 240 Nm
X
First gear 3.474 reduction
X
Final drive 3.66 reduction
X IRD reduction of 1.36 iirc
Front hub torque a theoretical 4150.1 Nm.
IRD rear pinion torque is close to 1298 Nm.
As can be seen. The numbers are quite large. This is one reason I believe the IRD fails so readily when the VCU begins to stiffen. Basically there isn't much reserve torque capacity in the bearings. Don't forget that the IRD bearings and gears are receiving hub torque. This is where the Freelander is different to larger LR models with a separate transfer box. In those the final drive ratio is after the TB . This eases torque at the TB to about 1/3 rd of the wheel hub torque.
Sorry Hippo. I don't have my Freelander anymore. However I'm confident that I can post up some V6 Freelander figures on Friday evening.

Nodge68 said:

Sorry B34R but you missed the final drive ratio off your equation.

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You are, of course quite correct, my bad!

I went and did something interesting though that @Hippo might be interested, mainly because I'm sad and kinda like math problems.
I've gone and created a hippo drive train simulator in excel...
The first half of it is purely setting up the gearbox ratios, as follows:

The first table is all about the pure gearbox ratios - gears and final drives charted.
Table two combines the ratios and final drives by model of freelander - and also includes ird ratio to Front Wheel, ird ratio to Rear Wheel and ird ratio to PropShaft
I've then pulled the engine peak torque figures into a little table, double checked the IRD ratios match with the thread where @Hippo chopped up a couple of IRDs and counted teeth and plumbed in the diff ratios.

This then feeds into the second half of the sheet:

The first table on this one is engine ratios to shaft ratios F=Front Driveshaft, R=Rear Driveshaft, P=Propshaft.
Using the engine peak torque table from the beginning, plumbed in this shows by engine and gear what the maximum torques delivered to the front and rear wheels are and the propshaft in NM

"Shaft RPM Vs Engine RPM" is self explanatory, it was an example of the rotating speeds, which dynamically work themselves out based on the RPM that you enter into the RED box.

The cool bit is the final table "Shaft Slippage" which dynamically works out the shaft speeds on both sides of the VCU and then deltas it. I've used Hippos real world tyre measurement to calculate the MPH.
Front propshaft rpm is calculated from pure ratios, this is fed from the engine RPM and fed through the gearbox ratios so we are assuming that the vehicle speed is set by the front axle as that's where the power is delivered from in engine RPM.
Rear propshaft is calculated by: Calculate front wheels RPM from engine speed -> assume front wheels are spinning at same speed as back wheels if VCU is functioning correctly -> multiply rear axle speed by rear diff ratio to give the prop output speed. All of this will calculate dynamically based on engine speed.

It's interesting of note that at motorway speeds the slippage gets quite bad - by the time you've got up to 70-80 mph the VCU is doing one slip rotation every 20-25 seconds... (note that different cars aren't slipping different amounts at the same ROAD speed - they're slipping different amount at the same ENGINE speed - eyeball the speed column before looking at the slippage RPM.)

If anyone wants a copy of this spreadsheet I'm happy to hand it out for tinkering, unless you're all not as sad as me!

@60mph I think the vcu slips 1 full rev every 125 revs of the rear prop when using the 0.8% ratio of front to rear prop.
Is that what you get?
Naturally this doesn't take out any incurred change by the front tyre "working radius" being smaller due to more weight at the front.

sorry to ask but why is the bonnet so heavy
compared to a disco or fender,it weighs a
bloody ton on its own.
regards stan.

stannswhite said:

sorry to ask but why is the bonnet so heavy
compared to a disco or fender,it weighs a
bloody ton on its own.
regards stan.

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I think they make them stronger so you can stand on them. Why you want to do this is beyond me as you would damage the paint work. There's a lot of air pressure on the bonnet at high speed too. With the FL being a premium vehicle they try to make things more solid.

Hippo said:

I think they make them stronger so you can stand on them. Why you want to do this is beyond me as you would damage the paint work. There's a lot of air pressure on the bonnet at high speed too. With the FL being a premium vehicle they try to make things more solid.

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or they make weight savings with ali panels, on other models that have considerable weight in the drive train plus chassis

jamesmartin said:

or they make weight savings with ali panels, on other models that have considerable weight in the drive train plus chassis

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On the factory tour they said the current steel's were welded but the newer models coming through are aluminimunin with rivit's and glue holding them together. Hence knocking hundreds of kg oft the weight. Rivit and glue is stronger. Glue is said to be baked/set at the same time they bake the paint to harden it. Modern technology eh.

Hippo said:

On the factory tour they said the current steel's were welded but the newer models coming through are aluminimunin with rivit's and glue holding them together. Hence knocking hundreds of kg oft the weight. Rivit and glue is stronger. Glue is said to be baked/set at the same time they bake the paint to harden it. Modern technology eh.

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very believable

measurements as requested:
'98 FL1, K series 1.8, 5 door 200km+ - only external accessories = t'bar and nudge bar with spot lamps.
Tyre pressures all 29lb, tyres = Bridgestone A/T 697 205/70/15. Full fuel tank and no luggage to speak of.
F'right = 342mm
R'right = 348mm
difference front to rear = 6mm

Hippo said:

@60mph I think the vcu slips 1 full rev every 125 revs of the rear prop when using the 0.8% ratio of front to rear prop.
Is that what you get?
Naturally this doesn't take out any incurred change by the front tyre "working radius" being smaller due to more weight at the front.

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Near as damnit, 1:122.34 manual box 1:495.60 Automatic

However, as I'm sad, I've made another sheet up *drumroll*
I give you the tyre size vs speed to slip rpm calculator!

Fuelled by Monday morning coffee and a touch of boredom.

Again, happy to give this away!

I've realised that I may have made a bad assumption in the original sheet which I'll correct, I *think* the TD4 auto shares the same IRD as the V6 after @dfossil contacted me.

Have you felt the weight of the Discovery 3 bonnet? It's alloy but weighs more than the Freelander steel bonnet

B34R said:

...I've realised that I may have made a bad assumption in the original sheet which I'll correct, I *think* the TD4 auto shares the same IRD as the V6 after @dfossil contacted me.

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It's always been said the v6 ird ratio is different to all others, and all the rest have ratio's which are the same. This would make the Td4 manual and Td4 auto ird ratio's the same. This could be mistaken history but if they have different ratio's how do you know this?

Hippo said:

It's always been said the v6 ird ratio is different to all others, and all the rest have ratio's which are the same. This would make the Td4 manual and Td4 auto ird ratio's the same. This could be mistaken history but if they have different ratio's how do you know this?

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Looking at the rimmer bros website, they appear to state clearly that there are two IRDs 4 & 6 cylinder.

But, apparently @dfossil has been doing some manual tests and his TD4 auto pops a difference of about 0.2% - but I'm not sure sample sizes and other empirical data! We may need to get further details... and the part number off the case of their IRD!

The V6 is the only different ratio IRD. It drives the wheels at slightly higher ratio than the 4 cylinder variant. I suspect this was to make use of the extra torque available, giving a more relaxed cruising speed. This V6 ratio change is different the IRD pinion ratio change that was implemented to reduce failures.

htr said:

measurements as requested:
'98 FL1, K series 1.8, 5 door 200km+ - only external accessories = t'bar and nudge bar with spot lamps.
Tyre pressures all 29lb, tyres = Bridgestone A/T 697 205/70/15. Full fuel tank and no luggage to speak of.
F'right = 342mm
R'right = 348mm
difference front to rear = 6mm

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Snap!
2004 K series 5 door 109,000 miles, tow bar and electrics. Tyre pressures all 30psi, Hankook all terrain and all well worn.
F'right 344mm
R'right 350mm
Difference front to rear = 6mm

B34R said:

Looking at the rimmer bros website, they appear to state clearly that there are two IRDs 4 & 6 cylinder.

But, apparently @dfossil has been doing some manual tests and his TD4 auto pops a difference of about 0.2% - but I'm not sure sample sizes and other empirical data! We may need to get further details... and the part number off the case of their IRD!

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Unfortunately the paper label giving the IRD number has disintegrated - if you have a look at post #33 you will see how I deduce its 0.2% difference - I did that half a dozen times with a consistent result. Interestingly the VCU is 2005 from it's number as is the car and is still in pretty good nick from my wheel up tests - so it's reasonable to suppose it is the original fitment and that the IRD may be so too.

If someone would like to do the same test on a TD4 Manual we can compare - it's even easier to do than the one wheel up test (given two jacks - and wedges) and another TD4 Auto owner might see if he gets the same result as me.

dfossil said:

...
So - Hippo - are we seeing here their thinking behind reducing the drive ratio difference from 0.8% to 0.2%? - Feels right.

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I don't think this gives the correct results.

dfossil said:

Unfortunately the paper label giving the IRD number has disintegrated - if you have a look at post #33 you will see how I deduce its 0.2% difference - I did that half a dozen times with a consistent result. Interestingly the VCU is 2005 from it's number as is the car and is still in pretty good nick from my wheel up tests - so it's reasonable to suppose it is the original fitment and that the IRD may be so too.

If someone would like to do the same test on a TD4 Manual we can compare - it's even easier to do than the one wheel up test (given two jacks - and wedges) and another TD4 Auto owner might see if he gets the same result as me.

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When lifting the wheels on one side only yer measuring from that wheel to the prop, which is different to measuring both wheels turning on the lifted axle pair to the prop. Hence why I think yer results show 0.2 instead of 0.8 which is what I think it should be. Reason for this is the turning goes through the sun gears in the diff instead of the crown wheel.