well if you was to turn the engine off at 70mph your steering lock would most likely come on, your brakes wouldn work properly as your servo wouldnt be on, and really cant be good for your engine and transmission full stop

well if you had a separate switch for the ignition the steering lock wouldn't be an issue. if the servo, vacuum pipes and non-return valve were working, you'd be able to depress the pedal at least twice before the vacuum would run out.

i can understand why it would be bad for a turbocharged engine as the oil will over heat and leave deposits which will eventually damage the turbo but there are ways around this.

also heat soak can be an issue for the engine itself but you'd get the same problems if you stopped the engine after a long drive.

as for the transmission on an automatic it can be damaging as they use a oil pump inside the box that is driven by the engine which feeds the bearings, gears, control valves etc. as for a manual they don't have the same issues.

if you match the revs correctly then let the clutch out, clutch wear would be minimal as well as reducing strain on the gearbox

Yes, but it's still a (small) factor to consider. Turning engine off = not a good plan, but at least for heatsoak concerns there would be decent airflow in the bay - at least better than when stopping the car after a drive.

get a diesel

get a diesel

get a small petrol...new mazda 2's will do 50mpg from a petrol...and its cheaper than a tractor.

I still don't get the great love everyone has with diesel.

They sound awful. vibrate horribly (which can result in diesel penis), aren't much if any of a saving over an equivalent petrol car and they are still slow compared to petrol too (Don't even try and argue this).

As said above get a small petrol, they are cheaper to buy than a diesel, cheaper to fill up, give just as good mpg figures and cheaper to tax.

Oh and about the clutch wear thing above...no one ever heard of matching revs when changing down? If its good enough for rally drivers (Heel-toe) then its good enough for me.

Yeah diesels aren't that economical. Especially when people sit at cruising speeds on the turbo.

If I'm very careful I can get 50mpg from my 1.8 Golf GTI. Like they said on Top Gear, "it's not what you drive, it's how you drive it".

Leave plenty of room between you and the car in front, and read the traffic, so you don't have to brake even when they do. If you use the brakes, you were obviously driving too fast in the first place. Just practicing this one principal alone will teach you well.

No sudden movements. You don't wanna feel the car speed up or slow down. Build up speed by teasing the throttle very gently, don't ask the engine to push more than 10% more than it already is doing - you should never need the throttle pedal to be more than a third of the way down - you can still reach 70mph like this.

Yes, keep the revs right down, but not so much that it's labouring - like if 4th is less strain than 5th in traffic. I do 30 zones in 5th to hold speed at almost idle, but drop down to accelerate even very gently after a village or to take a hill.

Keep to your average speed. Keep it consistent. Flow like water in a pipe. Use your now bigger margin to adjust your progress gently.

Do all this safely - it may be more economical to maintain your speed through a corner, but not if you're gonna crash into something when you get around it! But turning does increase friction, so steering hard does create a braking effect in itself. Therefore you can let the steering brake you down through a corner instead of braking before it and then using the accelerator to get around it.

Beware of any different driving style you may promote. Lifting off the throttle in a downhill corner may prove to be the most economical way around it, but you may run the risk of loosing grip at the back if it's wet.

Also beware of how you are judged by other motorists - if you're approaching a large roundabout at only 30mph they may not expect you to carry that speed over it!

Leave plenty of room between you and the car in front, and read the traffic, so you don't have to brake even when they do. If you use the brakes, you were obviously driving too fast in the first place. Just practicing this one principal alone will teach you well.

No sudden movements. You don't wanna feel the car speed up or slow down. Build up speed by teasing the throttle very gently, don't ask the engine to push more than 10% more than it already is doing - you should never need the throttle pedal to be more than a third of the way down - you can still reach 70mph like this.

Yes, keep the revs right down, but not so much that it's labouring - like if 4th is less strain than 5th in traffic. I do 30 zones in 5th to hold speed at almost idle, but drop down to accelerate even very gently after a village or to take a hill.

Keep to your average speed. Keep it consistent. Flow like water in a pipe. Use your now bigger margin to adjust your progress gently.

Do all this safely - it may be more economical to maintain your speed through a corner, but not if you're gonna crash into something when you get around it! But turning does increase friction, so steering hard does create a braking effect in itself. Therefore you can let the steering brake you down through a corner instead of braking before it and then using the accelerator to get around it.

Beware of any different driving style you may promote. Lifting off the throttle in a downhill corner may prove to be the most economical way around it, but you may run the risk of loosing grip at the back if it's wet.

Also beware of how you are judged by other motorists - if you're approaching a large roundabout at only 30mph they may not expect you to carry that speed over it!

Very true, just keeping to a clean constant driving style helps I think. Traffic plays a major part in my fuel consumption, yesterday I was in stop start traffic for half an hour and used well over £5 worth of fuel.

What i tend to do when driving is i will coast down hills in neutral.

Say there is no difference between fuel consumption at idle and fuel consumption under gear braking: If you coast you build up speed, if you gear brake you are maintaining a constant speed.

So all in all you'd be using more fuel over the longer time that you are going down that descent.

Obviously this technique isn't all that great when you end up breaking the speed limit extensively.

I still don't get the great love everyone has with diesel.

They sound awful. vibrate horribly (which can result in diesel penis), aren't much if any of a saving over an equivalent petrol car and they are still slow compared to petrol too (Don't even try and argue this).

As said above get a small petrol, they are cheaper to buy than a diesel, cheaper to fill up, give just as good mpg figures and cheaper to tax.

Yeah diesels aren't that economical. Especially when people sit at cruising speeds on the turbo.

If I'm very careful I can get 50mpg from my 1.8 Golf GTI. Like they said on Top Gear, "it's not what you drive, it's how you drive it".

What? have either of you actually driven a new diesel?

My diesel engine is well balanced and makes less noise than my petrol polo, they do brilliant mpg figures even when booting it hard i average about 56mpg and that includes driving through city as well. Even when I "sit on the turbo" I still see at least 58mpg whilst doing over 80mph (private road ofc.)

But best of all they ARE actually quicker then most petrol cars (unless you have some turbo beast, but they generally drink petrol like its going out of fashion).

I have driven a 2.0 16v petrol mondeo, and can easily say that the diesel version pisses all over the petrol, and whilst still achieving 50+mpg. Try finding a big car which does 0-60mph in less than 10 seconds which gets more than 50mpg on average?

Another thing people say which is just short sighted prejudice is that all the power is between 2000rpm and 3000rpm. Sure its all in that range but with the massively long ratios I can go from 30 - 65mph in 3rd gear without changing... pretty much the same as any other car.

The only reason for people hating on diesels so much is because they are gutted they don't have one themselves and are stuck with mediocre underpowered thirsty petrol engines

Edited 12 October, 201114 yr by Matt Mk3loon

i like my derv. Its not very economical,probably cause I'm a retard at driving autos though. Saving up for an A5 tdi. gone are the days of diesels being slow and tractor sounding.

What i tend to do when driving is i will coast down hills in neutral.

Say there is no difference between fuel consumption at idle and fuel consumption under gear braking: If you coast you build up speed, if you gear brake you are maintaining a constant speed.

So all in all you'd be using more fuel over the longer time that you are going down that descent.

Obviously this technique isn't all that great when you end up breaking the speed limit extensively.

Really.....evidence please as there's plenty going against that comment.

Ok its not 0 fuel use but its a damn lot less thank running at idle.

I still don't get the great love everyone has with diesel.

They sound awful. vibrate horribly (which can result in diesel penis), aren't much if any of a saving over an equivalent petrol car and they are still slow compared to petrol too (Don't even try and argue this).

As said above get a small petrol, they are cheaper to buy than a diesel, cheaper to fill up, give just as good mpg figures and cheaper to tax.

Yeah diesels aren't that economical. Especially when people sit at cruising speeds on the turbo.

If I'm very careful I can get 50mpg from my 1.8 Golf GTI. Like they said on Top Gear, "it's not what you drive, it's how you drive it".

What? have either of you actually driven a new diesel?

My diesel engine is well balanced and makes less noise than my petrol polo, they do brilliant mpg figures even when booting it hard i average about 56mpg and that includes driving through city as well. Even when I "sit on the turbo" I still see at least 58mpg whilst doing over 80mph (private road ofc.)

But best of all they ARE actually quicker then most petrol cars (unless you have some turbo beast, but they generally drink petrol like its going out of fashion).

I have driven a 2.0 16v petrol mondeo, and can easily say that the diesel version pisses all over the petrol, and whilst still achieving 50+mpg. Try finding a big car which does 0-60mph in less than 10 seconds which gets more than 50mpg on average?

Another thing people say which is just short sighted prejudice is that all the power is between 2000rpm and 3000rpm. Sure its all in that range but with the massively long ratios I can go from 30 - 65mph in 3rd gear without changing... pretty much the same as any other car.

The only reason for people hating on diesels so much is because they are gutted they don't have one themselves and are stuck with mediocre underpowered thirsty petrol engines

Diesel cars are not quicker than petrol cars, its just a fact.

What you compared there is a 2.0TDCI Mondeo to a 2.0 16v Petrol Mondeo. One big advantage the diesel has over the petrol...it's fitted with a turbo!

Take two more equal cars like a Mk5 Golf GT TDI 170 and the Mk5 Golf GTI. Both a 2.0 16v turbo engine in the same car. Forgetting any technical things its just one runs on diesel and the other runs on petrol.

Which one is faster...the GTI obviously. A whole second quicker to 60mph.

I still don't get the great love everyone has with diesel.

They sound awful. vibrate horribly (which can result in diesel penis), aren't much if any of a saving over an equivalent petrol car and they are still slow compared to petrol too (Don't even try and argue this).

As said above get a small petrol, they are cheaper to buy than a diesel, cheaper to fill up, give just as good mpg figures and cheaper to tax.

Yeah diesels aren't that economical. Especially when people sit at cruising speeds on the turbo.

If I'm very careful I can get 50mpg from my 1.8 Golf GTI. Like they said on Top Gear, "it's not what you drive, it's how you drive it".

What? have either of you actually driven a new diesel?

My diesel engine is well balanced and makes less noise than my petrol polo, they do brilliant mpg figures even when booting it hard i average about 56mpg and that includes driving through city as well. Even when I "sit on the turbo" I still see at least 58mpg whilst doing over 80mph (private road ofc.)

But best of all they ARE actually quicker then most petrol cars (unless you have some turbo beast, but they generally drink petrol like its going out of fashion).

I have driven a 2.0 16v petrol mondeo, and can easily say that the diesel version pisses all over the petrol, and whilst still achieving 50+mpg. Try finding a big car which does 0-60mph in less than 10 seconds which gets more than 50mpg on average?

Another thing people say which is just short sighted prejudice is that all the power is between 2000rpm and 3000rpm. Sure its all in that range but with the massively long ratios I can go from 30 - 65mph in 3rd gear without changing... pretty much the same as any other car.

The only reason for people hating on diesels so much is because they are gutted they don't have one themselves and are stuck with mediocre underpowered thirsty petrol engines

Diesel cars are not quicker than petrol cars, its just a fact.

What you compared there is a 2.0TDCI Mondeo to a 2.0 16v Petrol Mondeo. One big advantage the diesel has over the petrol...it's fitted with a turbo!

Take two more equal cars like a Mk5 Golf GT TDI 170 and the Mk5 Golf GTI. Both a 2.0 16v turbo engine in the same car. Forgetting any technical things its just one runs on diesel and the other runs on petrol.

Which one is faster...the GTI obviously. A whole second quicker to 60mph.

Sure the mondy is fitted with a turbo, but it still does better MPG than the petrol (and is quicker)

And with the golf, yes its a whole second quicker but again look at the economy difference - petrol @ avg 35mpg - diesel @ avg 51mpg

I am genuinely very happy with my derv car, but i do get what you are saying. If I wanted something rapid I would most likely buy petrol, but as it stands modern TDI cars give a broader range of power and economy without sacrificing one thing for the other :)

My diesel engine is well balanced and makes less noise than my petrol polo

Thats because its full of sound deadening and because it's 10+ years more advanced than the engine in your polo, which was running on a 1970's block design. And because your actually mentally 35, (at least you look it in your 'deo)

But best of all they ARE actually quicker then most petrol cars (unless you have some turbo beast, but they generally drink petrol like its going out of fashion).

I have driven a 2.0 16v petrol mondeo, and can easily say that the diesel version pisses all over the petrol, and whilst still achieving 50+mpg. Try finding a big car which does 0-60mph in less than 10 seconds which gets more than 50mpg on average?

No they're not, they feel quick because you have a turbo providing boost with super short gears which run out at circa 3.5k.

The amount of times my long ratio 4 speed 3D gearbox laughs in the face of "modern diesels" and thats strapped to an engine that runs like a sack of shit, i'd be suprised if it was in excess 0f 40whp. But my golfs doing 80mph in 3rd gear at 5k, with another 1.5-2k revs available.

I had the delight of driving a 69ps straight diesel caddy van for a week. Utterly slow as fuck and super short gears in 5th at 90 its at 4k. Was not impressed and thats displacing 1900cc's!

Anyway to the point, you only need two mirrors by law, this includes the rear-view mirror. So take one off, less drag, better fuel economy. You'd be a fool not to!

Edited 13 October, 201114 yr by randombadger69

Matt, seriously..

"Diesels have a broader range of power"? What engines have you been driving!? Because petrols i've driven tend to give a more consistent power delivery between 2k -6k but turbo diesels are typically weaker at 2k and have given up by 4k. What's so much broader about that..?

Long gearing is just another unfair tool on top of turbos, chosen to help diesels match petrols.

I've put long gearing in the 6n, and in 4th that pulls reasonably well from 30mph to over 100mph - look mother, no turbo!

I wouldn't be so harsh, but half the reason i gave Peugeot back our '09 207 diesel (that we had from new) is that it was not only hard work to drive quickly because it ran out of steam so quickly and i spent half the time changing gear, but also that being a diesel it churned out black soot whilst being hammered on-boost.

Plus, despite being a brand new diesel car, it couldn't manage the economy of the MK2 Polo 1.6 16v on carbs. So it wasn't worth the money.

Diesels feel fast because you get a boost of the turbo, but it's short lived and everyone behind you chokes in black soot.

They're shit. And this coming from someone who's reluctantly agreed to buy an '02 MK4 Golf TDi because the mrs misses the 207. We get it on the 18th dec, when her mate moves house.

Well i won't be driving the thing, apart from when i have to take the family away once a year..

What i tend to do when driving is i will coast down hills in neutral.

Say there is no difference between fuel consumption at idle and fuel consumption under gear braking: If you coast you build up speed, if you gear brake you are maintaining a constant speed.

So all in all you'd be using more fuel over the longer time that you are going down that descent.

Obviously this technique isn't all that great when you end up breaking the speed limit extensively.

Really.....evidence please as there's plenty going against that comment.

Ok its not 0 fuel use but its a damn lot less thank running at idle.

What i was doing was disregarding the difference in consumption between idle and gear braking at higher revs.

But the saving comes in terms of the time that your car is running. If you coast her on down the hill, less resistance from the engine, down the hill faster. Same mileage, less fuel. Slightly.

To be honest there's not a whole lot of situations where it will really work all that well..

Mike

Yeah diesels aren't that economical. Especially when people sit at cruising speeds on the turbo.

If I'm very careful I can get 50mpg from my 1.8 Golf GTI. Like they said on Top Gear, "it's not what you drive, it's how you drive it".

I think you'l find that a turbo can actually increase fuel economy on a diesel. Due to the way combustion works, stoichiometry need not be maintained in a diesel as in a petrol. Therefore more air can be added, but you can get away with running them 'lean'

Nice, aren't diesels jetted lean anyway? Usually when you see a performance 306 Dturbo (hot favourite in N.I.) They billow black smoke out the exhaust.. Suggesting that correct jetting is richer?

This is only a guess, IMO diesel = disease-l :)

DON'T USE SUPERMARKET PETROL....ESPECIALLY MORRISONS :lol:

Edited 14 October, 201114 yr by buster.g40

Has anyone thought about LPG conversions? (autogassolutions)

whys everyone moaning about speed or accel, if you wanna go fast accept you aint gonna get good mpg.

a lot of diesels dont make the money back over their life cycle due to extra purchase cost and fuelling cost etc.

sit in the slipstream of a truck on the motorway if you want good mpg. barely any throttle and youll be at a consistent speed

also, its probably cheaper for the OP to drive a little more economically than go out and buy a new modern diesel and tax and insure it.....whys everyone having a bitch fit lmao

^^^ The G40 that won first place at this years Polo Show,owned by CHRIS2911 has an LPG conversion.

Edited 14 October, 201114 yr by buster.g40