Looking at Hyundai's 1.6 T-GDI engine's spec (used in their Tucson model), it seems turbo petrol engine produces same flat torque till 4500 RPM while their 1.6 CRDi's torque curve falls after 2500 RPM.
So, do the turbo petrol engines wipe out diesel's torque advantage entirely?
Why would someone buy diesel over turbo-petrol?
|
|
How do their mpgs compare?
|
Do you mean the maximum torque from both engines is the same, but that the petrol one sustains it to a much higher engine speed? If so, then yes, the petrol engine would appear (on paper) to be the better choice.
But really? I'd expect maybe 280 Nm from a modern 1.6 TD. A 1.6 petrol would need some serious boost to achieve that. Can you quote us the details?
|
If you read the specifications, including the consistent torque output, for the VW 1.4-litre 170PS TSi engine (Twin Charged) in my Jetta, you'll appreciate VW's thinking (the TSi engines proved Europe's top engine over several years):
tinyurl.com/2vscslr
This engine was also used in the Golf GT, which proved slightly quicker off the mark over the saloon.
|
You can have a look at the specs here.
www.hyundai.co.uk/new-cars/tucson
|
|
OK, you're comparing the top-spec mummy-in-a-hurry 1.6 petrol engine (265Nm, 177hp) with the that'll-do mummy-in-the-way 1.6 diesel (280Nm, 116hp.) Apples and doormats.
Last edited by: WillDeBeest on Mon 5 Oct 15 at 12:49
|
>> OK, you're comparing the top-spec mummy-in-a-hurry 1.6 petrol engine (265Nm, 177hp)
...which does 28.2mpg on the urban cycle (30.7 for the auto)
>> with the that'll-do mummy-in-the-way 1.6 diesel (280Nm, 116hp.)
...which does 52.3mpg. More torque, and a lot more mpg (even allowing for 'artificial' tests).
(BTW my A3 is a turbo petrol, and I like it.)
Last edited by: Focusless on Mon 5 Oct 15 at 13:16
|
|
My A3 is also a 1.4 turbo petrol and I also like it. It has 250Nm of torque but only 150PS.
|
Yes, but how did you come to choose it, and how does it compare with the Passat CC you had before?
};---)
|
How did I come to choose it?
(1) I don't do huge miles so mpg was not a huge factor. But it was one. In real world driving the 1.4 turbo isn't that far off the mpg I got from the 170PS diesel in the Passat CC.
(2) The official CO2 emissions when I ordered the A3 was 109g/km (it has now gone up but I should be okay) and so the BIK rate was a fair bit lower than a diesel Passat, especially as there was no 3% BIK charge on top.
(3) The monthly rental was a little lower than a similar spec'd Passat (not CC)
(4) I quite like having a slightly smaller saloon.
If I was ordering now, depending on monthly rental, I'd consider the new A4. When I get to order there won't be a 3% BIK charge for diesel either. Although a Passat GTE might be cheaper overall. Who knows what will happen by early 2017.
Compared the Passat CC, I'd say I prefer it. The interior is really a nice place to be. Although I'd say the seats in the Passat CC were nicer with softer leather (both are nappa). And I like the DSG more than I thought I might.
|
Damn, that was too easy.
};---)
|
Torque comparisons are nearly irrelevant with a CVT.. or 7speed auto gearbox
The way the NOX debate/findings are going... the EC auto industry and its regulators are going to resemble FIFA: obviously corrupt and no-one believes a word they say.
|
If you don't mind I shall stick with my normally aspirated straight six. I have no idea of torque figures but it is quite happy trundling round in 5th at low speeds without any signs of strain. Obviously for quick acceleration I drop it into third, or even second, and by the time it's red lined I'm almost at V1, rotate speeds.
Otoh my ex has a 2.0 straight 6 in her Lexus IS . A totally different beast, which is impossible to drive around at low speeds, say 40, in anything higher than 4th. And it's slow to pick up, only 150 horses I think. Beautifully put together though, still squeak & rattle free after 12 years. Nothing ever gone wrong on it in the 11 years she has owned it.
When the time comes to change, if I cannot justify the cost of a 4yo 328 Touring I might consider the VW/Audi group 1.4 petrol turbo as people on here seem happy with it.
|
>> Why would someone buy diesel over turbo-petrol?
Maybe they like to drive around making more noise and smoke?
|
My aforementioned 170PS (168bhp) 1.4 petrol unit is very flexible in fifth around town (manual gearbox) and pulls strongly even from 20mph or so.
I wanted the combination of the Jetta (2007 reg) and this particular engine in manual form, but there were only about a dozen sold in the UK over its short sales period (the 160PS replaced it with similar performance) - the rest were all DSGs and I don't like autos - so it took around three months to actually locate one. The majority want the Golf hatchback rather than saloons, a direct contrast to the US preference.
|
>> Torque comparisons are nearly irrelevant with a CVT.. or 7speed auto gearbox
One reason I considered the DSG when I got this car :-) I thought I'd miss the flexibility the 170PS diesel had when in higher gears. But when I was first looking the DSG equipped S-Tronic models for the A3 saloon had lower emissions than the manual. So the actual monthly additional cost for the DSG was £4 after tax.... then they upped the power to 150PS from 140PS and the manual car's emissions dropped to the same 109g/km.
Of course, since August the A3's have all had their emission figures raised. Mine has gone from 109g/km for CO2 to 113g/km I think. Probably because the original figures were based on smaller wheels? The Sport now has slightly lower emissions than my S-Line.
|
Torque comparisons are pointless.
Unless you add in engine speed and gearing.
Diesels are more efficient than petrols.
Subaru Forester 2.0 TD and 2.0 XT (petrol turbo) both produce max torque of 350Nm.
The petrol can rev to 6krpm, the diesel to 4krpm.
The petrol has 240PS the diesel 150PS.
Guess what's faster.
Guess what's more economical.
|
>> Guess what's more economical.
Skoda CityGo?
|
|
Torque is the means to get up to required speed in the shortest possible time through the gears and brake horse power the ability to reach top speed in the correct high gear (if I've not got it mixed up...!!)
|
|
You may buy horsepower but you drive torque.
|
Turbo Petrol vs Diesel - Focusless
