A thousand questions from a newbee (driving a diesel Land Rover) - Fuel Economy, Hypermiling, EcoModding News and Forum

yostumpy · 02-27-2012, 09:07 AM

Evenin' chaps. Not quite a thousand, but a fair few, not all at once tho'
(oops cant post a pic yet sorry folks, you'll have to guess)

This is Wallace, 1998 land rover defender, 300tdi turbo deisel.
last tank 26.4mpg imp, before finding this forum, so hope to improve on that.
Found the site on sat, went for a drive on Sunday in our MY2000 998cc Toyota yaris. I'm quite a careful driver (I thought) and I usually eek 50mpg from yaris on shortist runs, but reading this and the tips section, I pumped up the tyres, and on a 30 mile return trip got a whopping 60.5mpg imp on the inboard pooter. I was quite impressed.

yes the land rover!
Q1) I know I cant fit a vacum guage to a deisel, but can I fit it into the vacum take off for the (removed)egr, the pipe comes out of the air filter housing, or is it still a nono.

Q2) whats the best way to drive a 2.5ltr turbo deisel, 4x4. its got no electro gizmos, and a purely mechanincal Bosch inj pump. Do I

A) drive with a heavy foot up to speed then ease off

b) drive with med right foot looking for 'no smoke ' using the torque of the motor, but not the revs

c) drive like there is a VG fitted, ie light load, higher rev, trying not to use the turbo, if you know what I mean.

I under stand that its a different technique from a petrol engine, and for the last month I tried to be as gentle as poss, but only managed 26.5mpg imp. But then I discovered you lot!!!!!!!! I've been reading so much my eyes hurt and my legs ache. I think I was doing all wrong, as my trip in the Yaris proves.
Wallace has a full safari type roof rack fitted which I do use some times, and I'm thinking of cutting off the side upstands 75mm so that its flat, and then cutting it into 3 parts, with the 3 legs at the rear staying on, the middle section thrown away, and the front 3 leg section easily removable, and place where its needed. but as I use the truck for work. Do you think the partial removal will improve matters? I know its not the best testing ground in the world, as my driving is rarely a repetative commute.

yostumpy · 02-27-2012, 09:21 AM

another question. There is a video clip of a chap who fitted a kill switch, (germany I think) and he accelerates up to ,and over speed, then kills the motor and coasts, BUT he keeps it in gear? surely the drag of the engine would slow him down very quickly. Presumably its a petol motor, because if you killed the fuel the pump solonid at 80km/h the and left it in gear, the pupmp, being mechanical, is still pumping, but running dry, so would therefore damage it?? Or am I barking up the wrong trousers??

jakobnev · 02-27-2012, 10:12 AM

The best way to accelerate with a TD is by simply flooring it and using the revs where it develops the most torque.

When not accelerating, neutral coasting can be used with good results when the engine is not needed.

MetroMPG · 02-27-2012, 11:05 AM

Quote:

Originally Posted by yostumpy

Wallace has a full safari type roof rack fitted which I do use some times, and I'm thinking of cutting off the side upstands 75mm so that its flat, and then cutting it into 3 parts, with the 3 legs at the rear staying on, the middle section thrown away, and the front 3 leg section easily removable, and place where its needed. but as I use the truck for work. Do you think the partial removal will improve matters? I know its not the best testing ground in the world, as my driving is rarely a repetative commute.

A photo is worth some words. (Google image search for your rack style might help us understand what you're suggesting.) It's worth taking off a roof rack when not needed. You will decrease both frontal area and drag coefficient of the truck.

Savings will vary. EG: you can see a ~3% change here: http://ecomodder.com/forum/showthrea...-6-a-6069.html

People can be funny about roof racks -- "removal-phobic". (Not saying that you are.)

I once recommended to a friend that he remove the rack from his new-to-him small hatchback car. (Keep in mind this friend is the type of person who is perpetually in debt and always complaining that he needs to find ways to economise.) I even did the math for him, pointing out how much gas and therefore money he'd save in a year (I think it was around $60). But he wouldn't take it off. Why? "Just in case" he needed to use it, it would have been a fussy job to re-install. I don't believe he ever has used it. That was about 3 years back, so $180 worth of fuel burned for nothing!

Anyway - welcome to the forum. Good luck with your efficiency efforts.

yostumpy · 02-27-2012, 11:18 AM

Quote:

Originally Posted by jakobnev

The best way to accelerate with a TD is by simply flooring it and using the revs where it develops the most torque.

When not accelerating, neutral coasting can be used with good results when the engine is not needed.

so mid range power then! ie no benifit to creeping up to speed gently with little throttle? I'm still abit blonde with regards to the workings of a turbo deisel. presumably when you hoof it (not too much) then your not overfueling it like a petrol then, ie all fuel is used. But do you actually mean 'floor it', as that kind of goes against my thinking.

yostumpy · 02-27-2012, 11:20 AM

Quote:

Originally Posted by MetroMPG

A photo is worth some words. (Google image search for your rack style might help us understand what you're suggesting.) It's worth taking off a roof rack when not needed. You will decrease both frontal area and drag coefficient of the truck.

People can be funny about roof racks -- "removal-phobic". (Not saying that you are.)

I once recommended to a friend that he remove the rack from his new-to-him small hatchback car. (Keep in mind this friend is the type of person who is perpetually in debt and always complaining that he needs to find ways to economise.) I even did the math for him, pointing out how much gas and therefore money he'd save in a year (I think it was around $60). But he wouldn't take it off. Why? "Just in case" he needed to use it, it would have been a fussy job to re-install. I don't believe he ever has used it. That was about 3 years back, so $180 worth of fuel burned for nothing!

Anyway - welcome to the forum. Good luck with your efficiency efforts.

cant post a pic till 've gone past 5, so should be able to now.

yostumpy · 02-27-2012, 11:21 AM

now i'll try

MetroMPG · 02-27-2012, 11:38 AM

Ah, OK.

So, to answer your question. Full removal is obviously best. Your plans for lowering & partial removal will help. How much, nobody can say for sure. So now you have to answer the question: how much work are you willing to put in for an unknown, but likely small percentage improvement?

If it were mine, I would do the work. But I'm well down the "efficiency is fun" rabbit hole.