vrs diesel v petrol

[vRSy]

Petrol heads nearly allays think that the extra 2php that they might have over their diesel cousins is inportant but blasting across difficult A and B roads, diesels are so superior so far as performance is concerned. Le Mans and other areas motor sports are now dominated by diesels. If they gave the nod to diesel technology then my guess is that Diesels would soon be dominating in other areas, once the preserve of petrol motors also. Diesel has come so far in such a short time. Outside of the truck industry, little comparative research and development has been spent on diesel. Diesel fuel contains more energy than does petrol, per unit volume. Tt stands to reason that it has the potential. It is the market holding it back. Few manufacturers have been prepared to throw the buck and turn their back on fashion. Why is it that when two cars of the same model, the performance orientated version has been made the petrol while the diesel offering is the detuned version. 2 L diesels could easily be pushing out well over 200bhp without any fuel penalty but they do not because the still want the misinformed, to be shelling out on their petrol ranges. One could turn around the statement above about, if costs were equal that everyone would buy the petrol. I would say the opposite would be true, if manufacturers stopped holding diesel back and allowed it to be developed for performance. Then who would buy petrol, if they were showed to be not only superior in the real world but on paper also. I think that I am right in thinking that BMW started the trend for more sporty diesel motors, with the 123d 330d & 335d. These cars are also so easily tuned to extract even grater outputs. It is possible to have performance and relative economy, so why buy a car that uses such a massive amount of additional fuel just to show an unimportant and marginal bhp gain, unless that is, unless you have shares in the oil industry. What is needed, is an enlightened public, to be demanding even more from diesel and then petrol would cease to exist practically, it is already only showing its head because diesel is artificially being held back. Manufacturers are trying to ring the neck out of petrol which really ought to just be allowed to die out.

for a starters you are very much uninformed about torque in the TFSI. Diesels have a massive spike of torque over about 2000rpm, which fools you into thinking the car pulls really hard, but runs out of puff really quick hence constantgear changing to make the most of it,

the std TFSI has completely flat torque curve from 1800rpm-5800rpm there is a 207Ibft for that whole period. flat torque curves are renowned as being the best delivery full stop. you might have this abundence of torque but i test drove both before i bought the TFSI and did not like how easy it was to light up the wheels in the diesel especially in the wet,

as for the le-mans cars the reason they hve wiped the floor @le mans s mainly due to the amount of extra time they can stay out lapping much more than th petrols. so over a prolonged period it makes a big deal.

And your on about diesels being detuned, you really do not have a clue. The K04 TFSI in stage 2+ form makes 360hp/350Ibft, thats 130HP over standard a k03 will hit 280Hp/330Ibft thats 83hp more than standard.

The TDIs dont tune up to that sort of output that easiily so they cant be that de-tuned. whatare you looking at with an exhaust 230hp possibly a few more.

and there is no way the TDI wil beat the vRS on in gear acceleration, it'd be close and not a walk over but the TFSI is undoubtably faster. even more so in the wet. TDIs suffer more wheel hop, more understeer and less traction. the TFSI does what it sdoes with less fuss and more smoothness so doesnt feel as fast,

simples

I liked both cars but as other guys have said IN MY OPINION i prefer the delivery of the petrol.

[psycholist]

If revving the engine out to the red line is such an attraction then why are people buying VAG petrol engines at all - the best most of them do is 6500 rpm AFAIK and that's not exactly high revving these days... Thanks to using a turbo they don't need to rev that high to hit a given power level, so they can be driven very much like diesels since they have plenty of low end torque and run out of steam rather than coming properly on song as you pass 6000 rpm. If I wanted a proper petrol engine I'd go for Honda's VTEC engines - no turbo to fail and they scream like motorbikes at high revs .

Since in Ireland diesel is 10c/litre cheaper than petrol (Which is a slightly more honest price given that diesel is fundamentally cheaper to refine from crude oil), break even mileage for a diesel is much lower in Ireland.

If I was into track days, never towed anything, didn't spend most long journeys sitting at the speed limit on cruise control and didn't have to pay for fuel I'd consider a petrol engine.

If Mercedes ever gets the compression ignition petrol engine sorted I'll be interested in petrol again though - half the reason petrol engines burn more fuel is that there's a minimum amount of fuel that must be injected to the cylinder before the spark ignition can create proper combustion in the first place. In diesels this is not the case, so diesels burn only the fuel they need by injecting it into air already hot enough to cause it to burn when the engine is partially loaded (Which is pretty much all the time the accelerator isn't floored). For a diesel under full load more fuel can be injected until no oxygen is left to be burned, same as for petrol.

[john999boy]

1 question

3 answers

98 ways to start WW3!

[harrylime]

Quite correct; looking quickly on www.parkers.co.uk at a 2007/07 vRS with 20,000 miles; the TFSI is worth (part exchange) £9,925 whilst the TDI is worth £10,410. That's a difference of virtually £500 clawed back against the £1,000 differential when new. On fuel costs with mpg and cost differences set over 9,000 miles pa I'd be surprised if the difference is more that a few hundred ££s.

More importantly IMHO why base your decision purely on costs? As others have already said you should get a test drive in both (I did) and decide which you would prefer to have as your car!

Good luck.

I'm in the market for an Octavia Scout and my last car was a 2004 330d. Stunning car in every respect , the engine was a complete jewel and can't be compared to the PD lump in the Octavia (Scout not available with CR engine). I won.t buy another BMW because they now arrogantly force people to have runflats, which is a flawed, expensive concept. My idea of a luxury car is one with a spare wheel so that I have choices at replacement time. I do around 10,000 miles a year so am torn on the petrol v diesel decision.. The price differential is around £1600 so it would take at least four years before I break even with a diesel. I am used to 40 mpg plus so the petrol would be a move in the wrong direction in terms of consumption. However, the deciding factor may be the DPF issue, which appears to be a bit of a hidden financial time bomb. One catastrophic failure would wipe out any savings the diesel makes over a five year period at a stroke. On top of this, widespread anxiety about DPF's (not common knowledge at the moment), could also have disastrous results in terms of perception and residuals for diesels. I think it is possible that the view will spead that previous advances in diesel technology are being reversed in the quest for lower emmissions. New BMW 6 cylinder diesels are nowhere near as smooth as the engine in my 04 model. From what I gather, diesels also do a little worse in other areas of reliability, including turbos, injectors, head gaskets, EGF valves etc. perhaps the additional stresses in diesel engines require more over engineering than the accountants who now run car firms are willing to pay for nowadays The PD engine is noisy, although based on my test drive it is not that objectionable, just honest diesel engineering noises, appropriate for a Skoda.. However,I do value refinement. When my 04 330d was on the move, I defy anyone to know it was a diesel, it was like a 6 cylinder petrol engine, it was that good. For all these reasons i am leaning towards a petrol (if I can find one,\ they are like hens' teeth). Even after all this, I still have to get past my (almost default) position that diesels are more desirable, because of the headline mpg figures. It feels like a brave decision to go petrol and puts one in a minority. The biggest single issue is driveability because I don't like to rev the nuts off cars ( in the BMW I could make very rapid progress and never exceed 2000 rpm),. Talk about flexibility, I could set off from rest in sixth, I tried it once to see if it would. I have heard that the new 1.8 TSI petrol engine is pretty torquey but there are none around to test drive. Also, I would imagine the steering would have a different feel with a lighter engine?This is why views on these forums (both sides of the camp) are so useful. keep\ them coming chaps

Edited 5 January, 2010 by harrylime

[prolfe]

Couldn't agree more with Babs on this one.....

Buy a petrol car if you enjoy driving and enjoy your cars.

If its for your ears then buy something with six cylinders or more. R32 maybe.

[Babs]

6-cylinder petrol ftw

Can't wait to hear mine on full chat on the rollers!

[Dr Zoidberg]

Quite correct; looking quickly on www.parkers.co.uk at a 2007/07 vRS with 20,000 miles; the TFSI is worth (part exchange) £9,925 whilst the TDI is worth £10,410. That's a difference of virtually £500 clawed back against the £1,000 differential when new. On fuel costs with mpg and cost differences set over 9,000 miles pa I'd be surprised if the difference is more that a few hundred ££s.

More importantly IMHO why base your decision purely on costs? As others have already said you should get a test drive in both (I did) and decide which you would prefer to have as your car!

Good luck.

At current fuel prices , and assuming 35mpg for the petrol and 45 for the diesel (not unrealistic figures in mixed driving) then you'll spend 1426 on the petrol and 1130 on the diesel over the course of 10000 miles , so almost £300 a year saving in fuel even at low mileages. It won't take long at all to recoup the £1000 premium for the oil-burner , and as you say if you get half that back at resale time then the break even point is about 16000 miles. Not 16000 miles a year , but 16000 miles.

The diesel *will* be cheaper to run for just about everyone (and my experience says that if the car is driven hard then the fuel savings will be even greater for the diesel) , but that's just one factor when chosing the car.

Personally I like the way diesels drive - they suit my driving style more than a revvy petrol engine - but I don't think there is a "right" answer for everyone for which is best and anyone insisting that it's black and white is deluding themselves.

[arbs]

petrol petrol petrol, that said i think thhe arguement for the love of a petrol engine is weakened when we are talking turbo petrol vs turbo diesel - its a lot different from comparing a big NA V8 or VTEC vs the TDi!

Edited 5 January, 2010 by arbs

[prolfe]

And see the lots of threads about Revo over-estimating "standard" figures. It makes them look better

I also found the CR I test drove was still a bit... agricultural...

Revo overestimating doesn't make revo look better. Overestimating makes their advertised gains would look tiny.

[mark_eire]

Here's a good advertisement for the great vag diesel engines..... the vRS Tdi in 10 years time!!

Sorry, couldn't resist, I know the vRS diesel isn't that bad!!!

[SlimAdy]

LPG ftw!

[Babs]

Revo overestimating doesn't make revo look better. Overestimating makes their advertised gains would look tiny.

Well, technically.

But Revo will advertise, for example... an engine with manufacturer spec of 150bhp, they say "our remaps give 200bhp", in comparision to other tuners saying "our remaps give 180bhp", and Revo's small print/dyno graphs might say "standard car gives 170bhp on the rollers".

The headline figure is more, but the actual gains are similar to others

[prolfe]

The figure being closer to 180/190 would also explain why the perfomance of the PD and CR is similar to the TFSI, don't you think? Afterall there is only 1.3 seconds difference through the gears 30-70mph.

Perhaps one day the diesels will sound better when on song.

[Raglits]

Will freely admit I chose to order the diesel VRs on cost grounds. I simply can't afford to run the petrol for the mileage I do - might be something to do with my right foot appearing to be made of lead (I'm down to about 25000 miles a year now and if the mileage drops much more then petrol will be on the radar next time...) In an ideal word, I'd either have a performance petrol saloon or two cars, a fastish diesel for everyday use and a petrol car for the fun days...

If I'm brutally honest, I prefer a large displacement petrol engine, but see the attraction of turbo charged smaller engines as they have plenty of useable power, are normally pretty easy to tune and typically weigh less than a big V8, meaning it's easier to balance the car's weight distribution, but for me, on my budget the diesel makes most sense as an only car and is still fast enough to be fun on the odd occasion I get the chance to be a hooligan...

Diesels are great for the everyday drive, and on the motorway where I spend a lot of time, they are superb but so is a petrol if you can afford to run it...

[Aspman]

The biggest single issue is driveability because I don't like to rev the nuts off cars ( in the BMW I could make very rapid progress and never exceed 2000 rpm),. Talk about flexibility, I could set off from rest in sixth, I tried it once to see if it would. I have heard that the new 1.8 TSI petrol engine is pretty torquey but there are none around to test drive. Also, I would imagine the steering would have a different feel with a lighter engine?This is why views on these forums (both sides of the camp) are so useful. keep\ them coming chaps

I think you'll be pleasantly surprised by the TFSI. You really don't need to rev the nuts off it to get it to go. It'll tootle along and accelerate in 6th at 30mph. No it won't have the torque of a 330 (a car I lusted after before I got the Octy but couldn't bear to pay £14k for a high mileage car that looked like it had been lived in by a tramp) but it's got a lot more than most petrol cars in the same price bracket.

35mpg is easily manageable in the Octy with normal driving.

I think the Octy is more of a budget GT/ fast family car rather than a 'hot hatch'.

The Derv will always be the sensible choice and you'll always lose more money with the petrol.

Edited 6 January, 2010 by Aspman

[Bezzy]

I chose diesel over petrol due to my mileage and running costs. Used to have a fiesta zetec s, and absolutely loved the noise and revving the nuts off it between gears. I do have to admit that whilst my vRS does not have such a nice noise it seems a hell of a lot quieter and saves me a mint in fuel and other costs, largely because I'm not revving the balls off it to listen to the beautiful sounding engine!

I'd still love another petrol car, but for me, in my current situation, its diesel all the way! If my mileage dropped by half then I'd consider switching again. Since swapping I aim to save £500 a year in fuel costs. Thats a hell of a lot of money to me!

I'm a bit on the fence to be honest. I love the pull and surge you get from a diesel, but as I said, I miss the noise of the petrol at high revs!

I'd advise you drive both, and consider you're economic situation and whether its likely to change in the next 3 or 4 years.

At the end of the day, you'll be sat in whichever you chose for 9,000 miles a year, so you need to have a car which is going to put a smile on your face, be it diesel or petrol! My vRS can still make me smile like the Fez did!