best mpg Land Cruisers? (1 Viewer)

[hedydd]

But the depreciation on the Juke will cost?!

And I'm sorry I've got to laugh!

Jamie

It will depreciate a maximum of £18,000.
My Land Cruiser 100 series will depreciate a maximum of £43,000, which is what I paid for it in 1998. If I bought a new 200 series today it would depreciate a maximum of nearer £65,000.

You might laugh [cruelly] but I actually quite like it and it makes far more sense than a similar RR Evoque at double the purchase price.

 

[Dougal]

I think I said exactly that without spending an hour on Google

Without getting out the popcorn it is true you can throw figures and specs all day long and we all know that those figures have altered (or can be made to alter) so you just cannot compare apples with apples when there are so many variables and the right foot is one of the biggest variable known to man.

Your no if's buts ect about internal friction are (IMHO ) also a little out of touch these days. A 4 cylinder engine of say 20 years ago would have had at least and perhaps more friction as a modern six cylinder engine of today, this would be due to different machining methods/better tolerance control, low pressure piston rings along with thinner contact areas again = less friction. Modern oils lubricate better so again less friction. Lets us go to heat loss to the water jacket in the modern diesel, nowadays the modern diesel is so efficient there is virtually NO heat loss, in fact manufacturers are fitting warm air (eberspacher ect) heaters to vehicles as there is no longer sufficient heat loss to the water jacket to warm the heater matrix up, witness the Ford Endura DE engine, it can run for a limited time WITHOUT water.

regards

Dave

What are these altered figures you are referring to?

Do you realise that peak engine efficiency (measured in BSFC) hasn't changed more than a few % in decades and that old school mechanical tdi engines are still comparable to the most current common rail versions?

What is different is the emissions levels have dropped hugely, the rpm range is much wider and power for displacement is getting ever higher.

My 25 year old 4 cyl diesel has peak efficiency of around 215 g/kwh. The last 1HD-FTE engines are similar. BMW's 200kw 6 cyl 3 litre tdi hits around 206 g/kwh.

The secondary heaters (usually reverse cycle air-con) is to provide fast heat incold low load conditions. Like being stuck in a traffic jam. That isn't a new phenomenon, very few diesels will reach operating temp at idle in the cold. This is worse when you are running smaller and smaller engines to again minimise internal friction. They don't have the same excess heat as bigger engines with more cylinders.
Any engine can run for a limited time without water.

It is only in relation to old idi engines that people think we have come a long way.

 

[jamie_scotland]

I agree it makes much more sense than the Evoque!

I guess my opinion is swayed by the fact that my current 80 has actually increased in value since I bought it 5 years ago. I paid £4000 for it and even though i've put 80k miles on it I got offered £5500 a couple of months back!

A neighbour buys a new mondeo every 3 years and often wonders how I can afford to drive the Land Cruiser at 25 mpg when his Mondeo does 40... He can't seem to grasp that the money he loses in depreciation more than covers the extra fuel

Jamie

 

[Dougal]

A neighbour buys a new mondeo every 3 years and often wonders how I can afford to drive the Land Cruiser at 25 mpg when his Mondeo does 40... He can't seem to grasp that the money he loses in depreciation more than covers the extra fuel

Jamie

Mostly I find someone who changes cars like that, it's for tax reasons. Usually a work car with the depreciation used to offset company tax and provide "benefits" to the driver which aren't taxable because their personal income is knocking on the next tax bracket and they don't want to go there.

Or they just really suck with money and maths.

 

[canucksafari]

Mostly I find someone who changes cars like that, it's for tax reasons. Usually a work car with the depreciation used to offset company tax and provide "benefits" to the driver which aren't taxable because their personal income is knocking on the next tax bracket and they don't want to go there.

Or they just really suck with money and maths.

That or they fall for the propaganda from the automotive industry and the greenies they have recruited. Funny, they never say how much greenhouse gas is released into the atmosphere to trash/recycle the old one and build and ship a replacement vehicle.

 

[kim]

That or they fall for the propaganda from the automotive industry and the greenies they have recruited. Funny, they never say how much greenhouse gas is released into the atmosphere to trash/recycle the old one and build and ship a replacement vehicle.

That is the argument that I use with the greenies.

Oh, and an equivalent replacement is a dodge caravan. Not happening!

 

[Dougal]

That or they fall for the propaganda from the automotive industry and the greenies they have recruited. Funny, they never say how much greenhouse gas is released into the atmosphere to trash/recycle the old one and build and ship a replacement vehicle.

I thought the scrappage schemes were a thinly veiled attempt at kick-starting the economy.
The greenies aren't the ones currently pushing emissions standards, it's governments worried about local air-quality rather than worldwide concerns.

 

[crushers]

no, the scrappage schemes are a leading up to the "fleet renewal" plan by the big 4. it has nothing to do with enviroment or economy.

as for local air quality ... it is about money. all governments ever care about is votes and money, don't kid yourself. anything the government pushes will lead to more money in the coffers and if you look beneath the veneer you will see the rotting core.

 

[kim]

That is the first time I have heard of the Big 4. Who's the fourth, assuming the Big 3 are GM, Ford, Chrysler.

 

[hedydd]

What are these altered figures you are referring to?

Do you realise that peak engine efficiency (measured in BSFC) hasn't changed more than a few % in decades and that old school mechanical tdi engines are still comparable to the most current common rail versions?

What is different is the emissions levels have dropped hugely, the rpm range is much wider and power for displacement is getting ever higher.

My 25 year old 4 cyl diesel has peak efficiency of around 215 g/kwh. The last 1HD-FTE engines are similar. BMW's 200kw 6 cyl 3 litre tdi hits around 206 g/kwh.

The secondary heaters (usually reverse cycle air-con) is to provide fast heat incold low load conditions. Like being stuck in a traffic jam. That isn't a new phenomenon, very few diesels will reach operating temp at idle in the cold. This is worse when you are running smaller and smaller engines to again minimise internal friction. They don't have the same excess heat as bigger engines with more cylinders.
Any engine can run for a limited time without water.

It is only in relation to old idi engines that people think we have come a long way.

I disagree. The figures you quote are specific fuel consumption figures and, as you hint, make no allowance for the fact that my Audi, for instance and in standard tune, now produces 220hp and 500Nm of torque from only three litres swept volume. This compares with 200hp and 400Nm from the 4.2 1HD-FTE.
The vehicles are not so far apart in weight or size, yet the tuned Audi that I run is now up to around 300hp and 600Nm and hits 100mph up a hill where the LC struggles to hit 70 at the same point, yet the Audi easily manages in excess of 30mpg and driven at an average of 10mph slower the LC seldom exceeds 23mpg-24 if very careful.
Not all the extra efficiency is down to the engine of course but I doubt if aerodynamics has much to do with it during normal driving around here either. Some is down to the Audi having a six speed auto, but most of it must be down to a more efficient engine.

This seems to be confirmed by the very latest design changes to the Audi engine which has lowered the compression ratio and altered the accuracy of the bores when the head is clamped on such that lower pressure piston rings can be fitted to lower overall pumping losses once again. Combined with a new eight speed transmission the combined official economy has now risen from just under 30mpg to in excess of 35mpg on the current version.

Again, I have mentioned that I have ordered a Nissan Juke with a 100hp 1.5 litre diesel engine. It has an official figure of just over 50mpg. There is a new 1.6 diesel out in the bigger and heavier Nissan Qashqai which is more powerful and far more torquey but yet exceeds the little Juke's fuel economy by some 6mpg, both with six speed manual transmissions.

Engines are getting more efficient. I have a lot to do with medium size heavy duty diesels. Tier2 and Tier3 engines have on average an optimum specific fuel consumption at around peak torque, commonly at 1400rpm, of around 210g/kW/h. New interim Tier4 [our european Stage 3b] have fuel consumptions of just over 190g/kW/h, which is around 10% greater fuel efficiency and over a broader working range than Tier2. Yes, they do need Adblue DEF, but this seldom exceeds 5%, so assuming that DEF costs the same per volume as diesel there is a net gain in fuel cost of 5%.

If bought in 1000litre IBC's the cost of DEF can actually be around half that of diesel fuel in the UK.
Audi and Mercedes and BMW are now selling SUV's in the USA fitted with Adblue/DEF systems but they also retain a degree of EGR as well, which my examples above do not. This, I believe, is in order to ensure that one charge of DEF lasts up to 15,000 miles at a far lower infusion rate than commonly used in trucks and tractors which have a DEF tank of just over 10% of the capacity of the main fuel tank on average and need topping up every second fuel stop or so.

 

[crushers]

hint, they bumped GM out of first place last year...

That is the first time I have heard of the Big 4. Who's the fourth, assuming the Big 3 are GM, Ford, Chrysler.

 

[Dougal]

no, the s****page schemes are a leading up to the "fleet renewal" plan by the big 4. it has nothing to do with enviroment or economy.

as for local air quality ... it is about money. all governments ever care about is votes and money, don't kid yourself. anything the government pushes will lead to more money in the coffers and if you look beneath the veneer you will see the rotting core.

I'm talking UK scrappage. Not US.
They don't have the same big 3 or 4 or whatever in the UK.

 

[kim]

hint, they bumped GM out of first place last year...

Worldwide, Toyota bumped GM. In the states, they haven't been number one. And last year, Honda and Toyota would be in 'the big 4'.

 

[Dougal]

I disagree. The figures you quote are specific fuel consumption figures and, as you hint, make no allowance for the fact that my Audi, for instance and in standard tune, now produces 220hp and 500Nm of torque from only three litres swept volume. This compares with 200hp and 400Nm from the 4.2 1HD-FTE.
The vehicles are not so far apart in weight or size, yet the tuned Audi that I run is now up to around 300hp and 600Nm and hits 100mph up a hill where the LC struggles to hit 70 at the same point, yet the Audi easily manages in excess of 30mpg and driven at an average of 10mph slower the LC seldom exceeds 23mpg-24 if very careful.

I'm not sure what you're getting at there. Your 3.0tdi has similar full-load BSFC to all the other good tdi's. Including the 1HD-FTE/292F.

The audi has vastly superior aerodynamics and gearing far better suited to the task than a landcruiser. While footprint and weight of the two vehicles might be similar, that is all.

This seems to be confirmed by the very latest design changes to the Audi engine which has lowered the compression ratio and altered the accuracy of the bores when the head is clamped on such that lower pressure piston rings can be fitted to lower overall pumping losses once again. Combined with a new eight speed transmission the combined official economy has now risen from just under 30mpg to in excess of 35mpg on the current version.

Lower compression ratio is about noise and vibration and allowing more boost. Engines with a lower compression ratio also require more boost to keep efficiency. Lowering the compression ratio alone costs you efficiency.

Engines are getting more efficient. I have a lot to do with medium size heavy duty diesels. Tier2 and Tier3 engines have on average an optimum specific fuel consumption at around peak torque, commonly at 1400rpm, of around 210g/kW/h. New interim Tier4 [our european Stage 3b] have fuel consumptions of just over 190g/kW/h, which is around 10% greater fuel efficiency and over a broader working range than Tier2. Yes, they do need Adblue DEF, but this seldom exceeds 5%, so assuming that DEF costs the same per volume as diesel there is a net gain in fuel cost of 5%.

Show me this BSFC chart with better than 190 g/kwh. VW tdi's hit 197g/kwh many years ago with a reverse-flow 2 valve engine. But that 197g/kwh point on the BSFC chart is tiny.

Ad-blue is about NOx emissions, it's used as an alternative or supplement to EGR. It is emissions control, not efficiency improvement.

 

[darthvincor]

About electronically controlled engines.
I'm very familiar with a car from the very early days of EFI, from about the mid 80s.
And based on reading the manual for that:
-lots of sensors have backups, for example, air flow sensor fails, throttle position sensor takes over.
-most sensors and EFI components last a long time.
-and finally even when every sensor and valve dies at once, the ECU can still operate in some kind of basic slave backup mode, with hard coded values to replace the normal input of sensors.

Point is, they seem designed to always remain driveable.

 

[Dave 2000]

Let's start again.

Combat Chuck:

back on topic:
it stands to reason that fewer cylinders means less space to fill with fuel, but at the cost of the additional power.

Dave 2000:

Fewer cylinders does not always mean you have less power, it's about how you design/build/tune/modify the engine that makes the power however, you might not like how the power is delivered.

Combat Chuck:

I'm a firm believer in the benefits of an inline 6 motor, but were I building a rig that I wanted to sip fuel, deliver consistent power, and run at lower revs for hours, I would definitely shell out for a solid 4-banger diesel.

Dave 2000:

I agree that more cylinders are beneficial in particular smoothness and perhaps torque at lower revolutions.
Originally Posted by Combat Chuck
back on topic:
it stands to reason that fewer cylinders means less space to fill with fuel, but at the cost of the additional power.
I'm a firm believer in the benefits of an inline 6 motor, but were I building a rig that I wanted to sip fuel, deliver consistent power, and run at lower revs for hours, I would definitely shell out for a solid 4-banger diesel.

Originally Posted by Combat Chuck
back on topic:
it stands to reason that fewer cylinders means less space to fill with fuel, but at the cost of the additional power.
I'm a firm believer in the benefits of an inline 6 motor, but were I building a rig that I wanted to sip fuel, deliver consistent power, and run at lower revs for hours, I would definitely shell out for a solid 4-banger diesel.


Originally Posted by Combat Chuck
back on topic:
it stands to reason that fewer cylinders means less space to fill with fuel, but at the cost of the additional power.
I'm a firm believer in the benefits of an inline 6 motor, but were I building a rig that I wanted to sip fuel, deliver consistent power, and run at lower revs for hours, I would definitely shell out for a solid 4-banger diesel.



Originally Posted by Dave 2000

It is all about how efficient an engine is, I often get similar mileage as friends well cared for TD5 Discovery, his engine is smaller in capacity and cylinders but his engine although more modern has to work harder to pull his car around.

As technology moves ever onwards we will see better use of the fuel that is put in to the engine hence vehicles with newer and better electronic controls are normally easier on consumption however, that advantage can be wiped out in an instant with the failure of a single electronic component. From the moment the tow truck is called to get you to the garage and then the cost of diagnostics (not always correct ) and then the cost of the replacement part plus fitting, add in the possiblity of taxi/car hire ect means I will be hanging on to my non electronic 80 for as long as I can!

Now Dougal what is incorrect about that statement?

Without wishing to appear condescending let's break it down so it is easier to understand, I will let you decide if they are true or false

Dave 2000:

It is all about how efficient an engine is True or False?

Dave 2000:

I often get similar mileage as friends well cared for TD5 Discovery, his engine is smaller in capacity and cylinders but his engine although more modern has to work harder to pull his car around. True or False?

Of course I will claim True for you as it is factual, and has been proven.

Dave 2000:

As technology moves ever onwards we will see better use of the fuel that is put in to the engine hence vehicles with newer and better electronic controls are normally easier on consumption.

True or False?

That advantage however can be wiped out in an instant with the failure of a single electronic component. From the moment the tow truck is called to get you to the garage and then the cost of diagnostics (not always correct ) and then the cost of the replacement part plus fitting, add in the possiblity of taxi/car hire ect

True or False?


Means I will be hanging on to my non electronic 80 for as long as I can!

True or False?

You already know the answer to that Dougal right?

Now, let me know which statement I made is false and justifies a reply that entailed you getting out the physics book. I am no way challenging your figures except to say it is what happens in the real world that counts.

regards

Dave

 

[Combat Chuck]

I agree it makes much more sense than the Evoque!
...

I'm pretty sure riding a Radio Flier wagon down a hill makes more sense than owning an Evoque.

 

[Dougal]

As technology moves ever onwards we will see better use of the fuel that is put in to the engine hence vehicles with newer and better electronic controls are normally easier on consumption however, that advantage can be wiped out in an instant with the failure of a single electronic component. From the moment the tow truck is called to get you to the garage and then the cost of diagnostics (not always correct ) and then the cost of the replacement part plus fitting, add in the possiblity of taxi/car hire ect means I will be hanging on to my non electronic 80 for as long as I can!

Now Dougal what is incorrect about that statement?

You are correlating an engines efficiency with electronic control and making the assumption that further electronic control will yield further benefits.
Where mechanical tdi engines have no problem matching an electronic engine for absolute efficiency.

The gains made in fuel consumption are the following.
1. Direct injection not only giving better thermal efficiency, but an engine strong enough to take lots of boost.
2. Variable geometry turbocharging to provide more boost over a wider operating range.
3. The use of higher pressure turbocharging to deliver more from smaller engines (aka downsizing).
4. Gearboxes strong enough and with enough ratios to get cruising rpm way down. Passenger diesel cars are cruising around 1700rpm now, the current tdi v8 rangerover is cruising at 1400rpm. Courtesy of an 8 speed ZF auto.

Without wishing to appear condescending let's break it down so it is easier to understand, I will let you decide if they are true or false

Dave 2000:

It is all about how efficient an engine is True or False?

Badly written.
It is about how effiicent an engine is at cruising loads.
4 cyls and 6 cyls are just as efficient at full load, but at lower loads the 6 has more internal friction, more heat loss and as a result lower efficiency. It's as simple as the internal heat loss and work loss being a bigger proportion of the total.
It's like trying to feed a family of 4 vs a family of 6. If you can keep all 6 working hard it's no different. But 6 doing the work of four gets expensive.

Dave 2000:

I often get similar mileage as friends well cared for TD5 Discovery, his engine is smaller in capacity and cylinders but his engine although more modern has to work harder to pull his car around. True or False?

Again badly written.
The engine doesn't "work harder". Such a concept doesn't exist with engines.
There is only the torque an engine produces, the conditions it does that under, how efficiently it produces it and how efficiently that power is put to the ground.

So it's false. A td5 does not and cannot work harder than a 1HD-T.
It's either a sick td5 or a badly driven one that drinks like an HD-T. Then again, "often get similar" means very little.

I must say, you've mastered the art of writing down your nose quite well. I hope you can keep it up a little longer.

 

[hedydd]

I'm talking UK scrappage. Not US.
They don't have the same big 3 or 4 or whatever in the UK.

There is no UK scrappage scheme. It finished about two or three years ago.

 

[hedydd]

You are correlating an engines efficiency with electronic control and making the assumption that further electronic control will yield further benefits.
Where mechanical tdi engines have no problem matching an electronic engine for absolute efficiency.

The gains made in fuel consumption are the following.
1. Direct injection not only giving better thermal efficiency, but an engine strong enough to take lots of boost.
2. Variable geometry turbocharging to provide more boost over a wider operating range.
3. The use of higher pressure turbocharging to deliver more from smaller engines (aka downsizing).
4. Gearboxes strong enough and with enough ratios to get cruising rpm way down. Passenger diesel cars are cruising around 1700rpm now, the current tdi v8 rangerover is cruising at 1400rpm. Courtesy of an 8 speed ZF auto.

The LC 100 series with four speed auto is very high geared and seldom revs more than 2400 in my hands. In fact it usually works in a band between 1400 and 2400, very seldom exceeding 3000 except when hammering it to overtake up hill.
The Audi tends to rev higher on average, although it too pulls well down to around 1400 pulling hard on a light throttle before it downshifts.
One important point you have missed is the fuel injection system which is now overwhelmingly of the common-rail type. Not only is the injection pressure up to between 1500bar to 2000bar, depending on model, but the injection is made in stages with full computer authority in real time to provide an optimum combustion.

That current vehicles have substantially better fuel consumption than previous models despite much higher power and torque from smaller engines along with added emission s*** like cats and particulate filters is a testimony to the designer's skill. There is better yet to come. If they increased the DEF while decreasing the EGR they could optimise the combustion further to improve the engine efficiency even more.
The latest US built Mercedes ML class engine is a prime example. They have improved many aspects of the engine design so that the new current model now has a combined economy figure nearly 20% better than the model from early this year. The same is true of the VW Touareg that uses the same Audi engine mentioned earlier.
Yes, a proportion of that increase comes from improvements to the whole drivetrain, but much of it, probably half, comes from increased engine efficiency. Again it has new pistons and rings along with a low friction coating for the bores, similar to Nicasil.

Badly written.
It is about how effiicent an engine is at cruising loads.
4 cyls and 6 cyls are just as efficient at full load, but at lower loads the 6 has more internal friction, more heat loss and as a result lower efficiency. It's as simple as the internal heat loss and work loss being a bigger proportion of the total.
It's like trying to feed a family of 4 vs a family of 6. If you can keep all 6 working hard it's no different. But 6 doing the work of four gets expensive.



Again badly written.
The engine doesn't "work harder". Such a concept doesn't exist with engines.
There is only the torque an engine produces, the conditions it does that under, how efficiently it produces it and how efficiently that power is put to the ground.

So it's false. A td5 does not and cannot work harder than a 1HD-T.
It's either a sick td5 or a badly driven one that drinks like an HD-T. Then again, "often get similar" means very little.

I agree with that.