is it a myth or reality that one is better than the other....?

i believe that both have their pros and cons...

i list some obvious ones:

Diesel

Diesel is becoming more popular, due to its efficiency benefits over petrol and its lower CO2 emissions.

Pros:

• Stays in each gear longer, helping with acceleration and reducing the need for gear changing

• High engine efficiency

• Lower CO2 emissions

• Some high performance fuels are available in diesel

Cons:

• Diesel engines are louder than their petrol counterparts

• Results in a less smooth ride

• More expensive than petrol by a couple of pence

• Higher Nitrogen Oxide (an air pollutant) emissions than petrol

Summary:

More environmentally friendly and economical for long distance drivers

Petrol

Still the best choice for performance when driving, petrol is the most popular fuel with motorists across the UK.

Pros:

• Responsive

• Quieter than diesel

• Petrol engines are generally cheap to repair

• Faster revving

Cons:

• Petrol engines are less environmentally-friendly than their diesel counterparts

• It’s non-renewable

• Produces more CO2 than other fuel types

just how does putting a different engine and fuel in a car result in a less smooth ride:confused:

Soon there will be a very small case for diesel.

Derv has peaked ages ago, petrol efficiency is improving.

A decent, modern turbo petrol will give more flexibility, more BHP, nearly the same mid-range torque, and nearly the same MPG and CO2 emmisions.

Both derv and petrol canbe replaced by renewable sources with minor tweaks to cars, so that argument is irrelevant

The only good thing about a diesel is the mpg

I'd not had it long admittedly, but trying to drive my car quick on the way home I was changing gear at about 4500rpm which brought me back to about 2500rpm meant I got a whole 2000ishrpm in which to play and to be honest it felt like I was spending more time having to change gear than I was spending in gear. my brother's remapped 1.8T has a far greater useable rev range.

There's no to take a PD diesel to 4500rpm, especially a 8 valve diesel.

Use the low down torque rather than horse power.

Higher NOX isn't true though; you try buying a newish (built in last 10 years) diesel that doesn't have an oxidising cat on it.

I'd not had it long admittedly, but trying to drive my car quick on the way home I was changing gear at about 4500rpm which brought me back to about 2500rpm meant I got a whole 2000ishrpm in which to play and to be honest it felt like I was spending more time having to change gear than I was spending in gear. my brother's remapped 1.8T has a far greater useable rev range.

Do you make a habit of red-lining petrol engines?

If so, do they actually drop from 6500 to under 3500 on a single shift?

Would have thought the only reason to buy diesel is money

Edited 12 March, 200917 yr by DGW
Pointless quote of OP deleted.

Do you make a habit of red-lining petrol engines?

If so, do they actually drop from 6500 to under 3500 on a single shift?

I do indeed make a habit of red-lining petrol engines, but it's been so damn long since I drive it I've no idea what speed the engine drops to on bengie's 1.8T but I'm sure it was making noticable/usable boost over a broader range of engine speeds than my 1.9TDI does

There's no to take a PD diesel to 4500rpm, especially a 8 valve diesel.

Use the low down torque rather than horse power.

I was changing gear where it felt like the car/engine was done, should I be shifting at something like 3000-3500rpm? that's even less fun than 4500 :( poxy diesels :thumbdwn:

Had (hot hatch performance) diesels for a few years

Golf TDI 150.

Vectra SRI CDTI 150BHP, running DTUK tuning box giving 190bhp

Now running a Octy 2 VRS TFSI.

As said above both have pros and cons and your budget and average miles will dictate whats best for you.

I used to do a 60 mile commute each day hence the diesels, then got stationed 8 miles from home, At this point I again could move to petrol with diesel being so much more expensive to fill up it made sense.

Also the initial outlay for a diesel is starting to outweigh the pro of more mpg as you have to do lots of miles.

I never thought I'd go back to petrol, when the price of diesel got up to 130+ per litre it was time to change. especially when the petrol vrs is now returning 33mpg every day.

My diesels were only 10 - 12 mpg better so it's cheaper for me to run the petrol......

I'd always be open to going back to diesel should my daily commute go up to 60 miles+ again as they were crackin cars and still put a smile on my face whenever I gave them the beans.

I do indeed make a habit of red-lining petrol engines, but it's been so damn long since I drive it I've no idea what speed the engine drops to on bengie's 1.8T but I'm sure it was making noticable/usable boost over a broader range of engine speeds than my 1.9TDI does

Yes and? You're not comparing like with like. The relevant point is not the width of the powerband, but how much road speed you can put on in that powerband. Since diesels are frequently geared 50% longer than petrols, you can actually put on the same road speed or more in the diesel's real power band (more like 1_500 to 4_500 anyway with a current or last gen VAG unit).

I was changing gear where it felt like the car/engine was done, should I be shifting at something like 3000-3500rpm? that's even less fun than 4500 :( poxy diesels :thumbdwn:

See above about road speed and where a TDi actually makes power from.

Agreed with road speeds etc, exception to this with the diesels must be in 1st and 2nd gear. they are next to useless if attempting to get to a high speed quickly.

The torque is a huge benefit if your pulling weight such as five adults or a caravan on a hillstart but mostly the very short 1st and 2nd gears can be quite annoying, especially in start stop traffic or motorway queues.

tak

I realise they're different and that there are adjustments to be made, but mine doesn't feel to be doing all that much at 1500rpm and I've just been told there's no point revving a PD as high as 4500rpm so at the moment it seems like I've got from about 2-2500 upto 3-3500 to play with.

when I was trying to keep up with bengie on our way home it felt like I was changing gear a whole lot more than I was accelerating in a gear which made a chore of what should have been a joy whereas motorway acceleration was seemingly effortless and I could drive away from him even when he'd got a run on me

Agreed with road speeds etc, exception to this with the diesels must be in 1st and 2nd gear. they are next to useless if attempting to get to a high speed quickly.

The torque is a huge benefit if your pulling weight such as five adults or a caravan on a hillstart but mostly the very short 1st and 2nd gears can be quite annoying, especially in start stop traffic or motorway queues.

tak

I find the reverse is true, and I can meander along in m/way jams at idle revs feet off in a turbodiesel. When the traffic speed starts picking up I'm left short-shifting to keep from ramming the gutless 16v petrol engined atmo motor in front of me!

You should have got a better engine than the 1.9, the 2.0 DSG gets round the gear changing and the power

I thought the 2.0 was 170bhp? so it has what, an extra 10bhp and very similar (peak) torque numbers? and an automatic diesel...no thanks

The 2.0 comes in 140bhp & 170bhp form & is 16v

They drive differently to a 1.9 8v.

I thought the 2.0 was 170bhp? so it has what, an extra 10bhp and very similar (peak) torque numbers? and an automatic diesel...no thanks

I didn't think Skoda had ever had the 1.9 160. Oh and DSG isn't an automatic so much as a clutchless manual that you can get to shift by itself if you want.

I like diesel because I am lazy. I think Diesel cars are easier to drive 'quickly'. I do alot of miles and like the fact that it requires less effort.

I didn't think Skoda had ever had the 1.9 160. Oh and DSG isn't an automatic so much as a clutchless manual that you can get to shift by itself if you want.

they didn't get the PD160, but that makes no odds to me tbh

I know that DSG is far from an auto box, I was being a wise guy

having driven a GM CDTi and heard lots about Ford TDCi cars, 16v diesels don't seem all that low down

Horses for corses and all that.

I've owened a good selection of both over the years and a lot of it's down to personal preferrence. Love the 1.9 TDI that's in the Fabia VRS and liked the same engine in 105bhp guise which I had in the Mk V Golf, not so keen on the 2.0TDI (170 bhp) that's in the Octavia VRS.

In terms of petrol engines the 2.0l TFSI is a stonker, probably the best engine I've ever had under the bonnet. But I've had some crap petrol engines in my time as well.... GM's 1.6 NA unit springs to mind.

So it's not quite as simple as deisel is better than petrol or vice versa IMHO

exactly Johnwg. After all it comes down to personal preference, use and driving style.

My driving style requires petrol though ....

Last thing I read, during the peak prices, unless you're doing 30k+/year then there is very little benefit in having a derv car if cost savings is the goal.

Car, fuel, and maintenance were cheaper. Was a Which? report IIRC.

Found this interesting. Huge differences between manuafacturers and for different models. Costwise it's maybe OK to go for a deisel if you buy carefully and keep the car for a good few years, though maybe not a Fiat Panda for 32 of them. I do like the relaxed motorway drive on the higher geared diesels.

Ford Mondeo Estate

2.0 TDCi Edge 5d

List price £20,640

Fuel consumption 47 mpg

Price per litre 100.0p

2.0 Edge 5d

Change:

List price £18,990

Fuel consumption 35 mpg

Price per litre 90.7p

Extra cost to buy £1,650

Saving per 1000 miles £21.08

Miles to break even 78,262

Time to break even

at 12,000 miles per year 7 years

:eek: