Tron, I was talking about where the reliability thing came from ie 15 years ago. My petrol's got no HT leads, ignition coils are built into the spark plug.
So no damp start problems, no mixture problems, no carburettor, no fuel quality issues, no spark plug issues, no HT leads etc etc etc.
But as has already been said, they have a turbo (Which needs expensive oil) and a stack of emissions kit to go wrong instead.
Whatever, when I did the sums, there's no way a diesel would have been cheaper to run, so we bought a petrol car. You've got to be doing 20k+ before it's worth it
And I simply don't like diesel engines in cars. I've driven a LOT of them as well, from most maufacturers, and recently I got to compare our petrol Focus with another Focus with the equivilent diesel engine in it.
The diesel car was like somebody had filled the front with lead and replaced the throttle cable with some old knicker elastic.
Whatever the NUMBERS say, to me a petrol engine feels crisper, keener, smoother. There's no turbo lag, no powerband: Dab the gas and get the power instantly, not wait for a second or two, get a huge rush of tourque and then have it die 1000rpm before the redline.
And the petrol Focus was notably better handling. It just felt lighter on the front and quicker and more accurate to turn in. More bite in the brakes too, and a slightly more supple ride. The heavier diesel engine really dulled the dynamics of the car.
It's the second back-to back test I've done like this, and the petrol car has won both times.......
You lot do realise that you have just totally ruined what was, for me at least, an easy choice at what I was going to get as a next car don't you?
I had it all lined up... part-ex my 4x4 for a five year old (max) Skoda Octavia estate diesel and drive off into the sunset smoking pipe and putting leather arm patches onto my tweed jacket.
I now find out that I might as well not both buying one because even the 56 mpg figures that parkers bandy around for the 1.9PD TDi version are going to cost me money because I do less than 15k a year.
So, you swines... What am I going to do now? Huh? It's taken me a year to think about selling my 4x4 and now it's gone totally out the window.
Turbos.. we are talking about old diesels here.. turbo just went in my old diesel that my neighbour now has.. after 185k miles. Can't really complain about that 🙂
, not wait for a second or two, get a huge rush of tourque and then have it die 1000rpm before the redline.
I invite you to come and drive my Passat 2.0 TDi. It categorically does NOT do this. Seriously, it pulls more and more up to the red line.
There is turbo lag, unless you leave the tranny in S mode, when there's none. As for handling, yep, agree. Personally I don't like the way you have to downshift in a petrol car to get it to accelerate, and I also don't like the way I have to fill up 30% more often 🙂
Oh and willard - MTFU, sell the chelsea tractor, get the Octy and enjoy torquey effortless motoring 🙂
Get an Octavia Scout 4x4 tuned for 180 bhp and get the best of both worlds 😉
I tell you what i like the look of - the new VAG 1.4 turbo engines - 140BHP, low emissions. Sure - you'll have to get 'em spinning for decent power, but there's something satisfying about low displacement turbo engines!
DrP
DrP, I often said to myself that someone should come up with a small turbo petrol engine - lo and behold VW did. Not bad for emissions but you've still got turbos to contend with which was one of the diesel disadvantages quoted above.
Yeah, I thought about the Scout, but given that most of my driving these days is on road and not on the farm (and it is _not_ a chelsea tractor by the way!) it seems pointless to have... Just another bit of transmission to haul around.
This really is no easier than it was six months ago. Maybe I should just buy another cheap Golf while I decide...
Having just got a used Golf GT TDi I have to say I love the torquey nature of a decent diesel. We do quite a lot of country lane stuff and the engine makes it so easy to go at a reasonable speed without having to rev the nuts off it - lovely for overtaking in short distances too.
I do a 7 mile round trip to school and back every morning and even over a short distance it averages 44mpg even when it's below freezing.
I've told myself I won't buy another petrol engined car 🙂
I've just gone from a petrol turbo Saab to a diesel turbo Saab and er.. er.. sorry I don't give shit! It's just a car!
Nor do I really... But I have a certain number of requirements that I have to meet.
1) Boot big enough for two spaniels, overall big enough to fit camping stuff, dogs and food in for a week. Bikes to be able to go in the back when dogs are not in there
2) Good fuel economy
3) Reliable
4) Comfortable on long drives
I'd like to add "exciting drive", "sporty", "off road ability" to that list, but let's be honest here... I don't care as long as it gets me to work daily, get's me back to Suffolk once in a while and down to Wiltshire once a month.
Ideas?
Personally I reper petrol, I had motorbikes before cars so the concept of changeing gear to accelerate doesn't bother me. Although I do miss being able to flick between gears without the clutch.
I'd love it if someone built engines designed for LPG, might not be very long lived, but 200bhp per liter would be fairly easily obtainable, although you'd have 2stroke sized power bands..
willard - no budget then! Must be a massive range, no wonder you're having trouble. 😉
Tinas, are you talking about increasing the compression ratio? Several companies are working on that for ethanol - with appropriate compression you can achieve high specific powers. I think Saab were looking at eccentric crankshaft bearings, kind of like an EBB for single speeds I suppose.. but then again if you have a turbo you can just up the boost which is what some older car enthusiasts have been doing, to get 300bhp from old Volvos I read somewhere.
Variable compression with atkinson miller cycle using solenoid valves.. very interesting.
I invite you to come and drive my Passat 2.0 TDi. It categorically does NOT do this. Seriously, it pulls more and more up to the red line.
Would that be the same 2.0Tdi engine sitting in the VW Eos sitting in our drive? The 140bhp one? (Belongs to the mother in law, we get to borrow it when she goes away)
Well, it's a gutless slug below about 1500rpm. (Our 1.6 Focus is more flexible) It's the engine I was thinking of when I wrote my last post. Horrible thing. The old 1.9Tdi she had before it was a far nicer engine, even though it didn't have the same headline power figures.
thisisnotaspoon I'd go for the 1.4 petrol personally.
I'd only buy the 1.9TDI if you were planning on owning it for its life. Sorry '90k just run in' doesnt count it for me. ALL engines are a lottery.
If you were keeping it 2-3yrs- 1.4 everytime.
Ah yes, budget... A sore point that. I'd like to say I could afford to go an spunk a wadge of cash on a second hand Cayenne diesel, but in reality I've got about 5k (maybe 6k with a following wind) to spend on something that should maybe last four years.
ditto molgrip's point on the 2.2 CDTi Honda engine. What a silly reviewer. I drive a different diesel car every week and my honda 2.2 beats them all hands down. It's the only one that feels like a petrol engine.
[i]There isn't enough diesel in the world to supply demand[/i]
You sound ever so slightly biased there because precisely the same point is true for petrol isn't it.
edit: oh sorry, would I reccommend a diesel engine? Every single time, whether it's for running around town or doing long motorway hauls. I'd never go back to petrol.
Would I buy a 90,000 1.9TDI Fabia for over 5k?
Would I ****.
would I buy a 90,000 1.9TDI VW Passat for 3.5k? Yes I would.
You've got to be crackers to spend that much on a high-miler Pope mobile. I drove one on holiday and hated it with a passion. The Panda they replaced it with was five-times better.
Pile of shit.
[i]Would I buy a 90,000 1.9TDI Fabia for over 5k?
Would I ****.
would I buy a 90,000 1.9TDI VW Passat for 3.5k? Yes I would[/i]
You realise they're *exactly* the same engine? Made in the same factory and everything....
Oh aye yeah. Everything else round it has been designed with different tolerances and for a different purpose.
Lets not forget one is a amalgamation of two different floor pans and is designed around smaller engines etc.
Why would anyone want a Roomster? Jez to the forum..... 😆
hora - MemberOh aye yeah. Everything else round it has been designed with different tolerances and for a different purpose.
you appear to post on anyhting to do with cars, but I get the impression that you know ****-all about them beyond reading What Car at the dentist and probably talking b*ll*cks about them with your recruitment colleagues.
Geronimo thats a stunning handbag. Do you own many?
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Call that a handbag?
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😆
Bloke at work has just suggested that I pretend I have kids already and buy a new Berlingo. FFS!! Me, buy a French car?
Besides, it looks fugly.
Well, it's a gutless slug below about 1500rpm
I guess there's something wrong with yours then, mine's fine. Maybe you just don't understand turbo lag?
I hired a petrol Mazda 2 at the weekend. It was incredibly slow, like back to the days of 1.0 Fiesta/Polos, and only got 43mpg. It was totally gutless below 1.5krpm AND above it. You could trundle along nice and smoothly in say 4th at 40mph - put your foot down, and nothing happened. At all. To get onto motorways and such you had to red line it in second.. relaxed capable driving I think not.
My Passat is about twice the size, far quicker, far more versatile and gets more MPG. So why do people like petrol again?
My Passat is about twice the size, far quicker, far more versatile and gets more MPG. So why do people like petrol again?
And costs much more to buy new than a base Mazda 2. What is the equivalent petrol Passat like?
Sure, MF - wasn't comparing value. I actually quite liked the Mazda. This is about the engine technology itself.
Here's a dynograph of a Passat 2.0 TDi
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Here's one for a Focus 1.6 Petrol
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TDi develops about 43kW at 1.5krpm, the petrol about 17kW. About two and a half times the power from the diesel at that speed. TDi develops about 280Nm of torque at the same speed, and the petrol about 105Nm. The TDi reaches pretty much max torque at about 1700rpm, and in normal driving engine speeds it's operating at max torque. Hence torquey driving. The petrol's torque curve is quite interstingly flat all through the rev range but the figures are very much lower than the diesel. Hence having to change down to get it to move much at any kind of speed.
Also note how the TDI's power increases all the way up to its red line.
My mum has a skoda fabia estate 1.9d, gives ugly a bad name but goes as fast as anyone needs a road car to go, handling is precise enough as long as your not driving like a **** and fuel economy seems good.
Going back a bit, me and the Mrs both had MK4 Golfs for a while!
She had 150bhp Gti version, did less miles than me and I had the 1.9tdi 150bhp version as a company car.
(both did not deserve the gti badge tbh).
But the diesel felt the quicker car on the road to drive in real everyday traffic scenarios.
Neither were great drivers cars tbh, but I guess its as close as you can get as a direct comparison to petrol/diesel debate.
Saying that, she was loaned a 180bhp Gti and that was closer, slightly quicker match for the tdi.
I guess there's something wrong with yours then, mine's fine. Maybe you just don't understand turbo lag?
Oh I do. Totally, 100% understand it. And THAT is PRECISELY why I don't like diesels. LAG! **slaps forehead**
I don't care what the numbers and the graphs say, I just care what it feels like when I twitch my right foot. At the end of the day, a petrol engine is more responsive than a turbo diesel. Tweak the throttle, and you get instant action. No matter how much power you get in a diesel, no matter where you are in the rev range, you've gotta send forms in triplicate to the engine when you want power. 😉 There's always that pause as the turbo spools up and the heavy old pistons slowly wind their speed up against that mahoosive compression. That's why, to me, diesel engines don't belong in sporty cars like said Eos.
I know I'm in the minority with this, but that suits me fine. I did the maths when we bought our car, and it wasn't worth getting a(nother) diesel financially, so we didn't. And it's lovely to have a smooth, quiet revvy little petrol engine again! 🙂
Molgrips, that graph shows the TDI's power falling off sharply before the red-line not increasing all the way.
Molgrips, that graph shows the TDI's power falling off sharply before the red-line not increasing all the way.
Yeah, that feels about right after driving one. 4k rpm and it's all over bar the shouting. 🙂
And here's a better comparison to the 2.0TDi VW graphs. A 2.0TSi - Petrol Turbo
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Not quite the same headline torque figure, but look at that huuuuge wide plateau of torque! 1700-5000rpm +!
Makes the diesel engine looke like a 2-stroke!
And the power figure murders the diesel. Bye Bye..... See ya, wouldn't wanna be ya!
😀
a different slat, just drove from Cheltenham to Chester via the A5 in my 1.9TDi and got an indicated 73mpg, find me any petrol car that would be remotely comfortable for that journey and give that sort of economy?
mrmo: What kind of speeds were you doing? I don't get anywhere near that in my 1.9tdi on an 80 mile motorway commute.
got 67mpg out of my 1.9 D partner at 70 on the dualer on a round trip without particularly trying to be fuel economic.
your arguement is mute for me PP ill take slow and powerless for that sort of return as long as i can do the speed limit
PeterPoddy - MemberAnd here's a better comparison to the 2.0TDi VW graphs. A 2.0TSi - Petrol Turbo
Exactly.
My petrol turbo also had a flat torque curve like that. It was fantastic to drive. My TD has a flat spot off tickover, a delay and then a lump of torque which gives a bit of shove, promises a lot ...and then fails to deliver as it dies off fairly quickly.
At ~2000rpm in high gears it does pull quite well. 80-100mph (where conditions allow) is quite quick probably as it stays in the 'powerband' for longer in higher gear, but at medium speeds on back roads it's not that quick.
I'd much prefer a non-turbo 3.0 V6 petrol, but the fuel costs are prohibitive. I'll stick to a tractor for now(and re-consider the petrol/diesel issue when I look to swap) and the purity of a motorbike, which is much more fun.
most of the M5 is 50limits now, then the bit around birmingham to the M54 more 50mph if lucky, more like 40mph, then 60 something on the dual carriageway sections.
I was traveling on the slow side, 60 something rather 70 something it just gives me something to think about on the commute.
Turbo petrols are good for driving, I agree. I thought this was a discussion about NA petrols which are the most common incarnation. I have said on other threads before how I like turbo petrols.
I just care what it feels like when I twitch my right foot
That's my point really - your right foot doesn't know what it's doing.
no matter where you are in the rev range, you've gotta send forms in triplicate to the engine when you want power
Kind of proves my point - you're kind of wrong there. If you are driving over a certain speed the turbo will always be spinning. I can get plenty of instant power from my engine just by keeping the revs up. That's what the S mode on the auto box does, in fat. And it's not fair to say that there's no power under 1.5krpm when the delay is caused by turbo lag not power flat spots. In a NA petrol (unless it's huge) you'll never go anywhere quickly from 1.5krpm ever, whereas by understanding the engine in a TDi you can take off.
And here's a better comparison to the 2.0TDi VW graphs. A 2.0TSi - Petrol Turbo
Do turbo petrols not have lag?
And anyway, why are you worried about the number of rpm? In say a Honda 2.2 CDTi if you just painted over the numbers on the tach with petrol ones you'd NEVER know the difference between it and a turbo petrol.
Molgrips, that graph shows the TDI's power falling off sharply before the red-line not increasing all the way.
That's the limiter. It does tail off *just* fractionally below the actual red line painted on the tach but so what? I was attempting to compare it to the older PD engines which are the ones with a big slug uner 3krpm then a long gradual tail which really is frustrating to drive with when you are trying to say overtake. But again, plenty of fun can be had if you aren't an idiot.
You seem somewhat obsessed with one specific driving style, and with some numbers. You seem to feel that unless the tach needle touches a 6 you haven't achieved something, regardless of how the engine's performed up til that point. Diesels can be just as fun and sporty if you aren't a complete numpty with the throttle.. 🙂
Only diesel disadvantages in my view (and experience) are:
More NOx/particlulate pollution
Heavier engine may affect handling if you are really into it
Higher cost
Increased energy cost in refining possibly.
So the limiter starts to kick in at 4000rpm yet the engine continues to rev to 4500. That's nearly 15% of the rev range. This is not caused by a limiter, but due to turbo constraints. Volkswagen have chosen a turbo that spools early but cannot flow enough air at above 4000rpm, and rightly so.
A petrol turbo will have lag, all turbos have lag. This means that you cannot get instant power. The lack of power below 1500rpm is not due to lag, but due to being below the turbo spool point. Lag and spool are different.
I can see an argument for Turbo Diesels, they provide acceptable performance with good economy. However, I would still spend my money on a larger capacity petrol engine with far better throttle response than either a turbo diesel or turbo petrol. If I were to do more miles I may consider a diesel, but I find petrol engines both more relaxing and more enjoyable to drive.
Not sure you are right about that, Harmitans. The car I fiddled with most was a 1.9 TD IDI all mechanical engine. The limiter was a compound spring arrangement that was set up to gradually reduce fuelling as you approached the red line. One of the favourite mods was to remove the softer of the two springs so that it kept on pulling. Only problem then was that it felt like hitting a wall as you hit the limiter. I think that maybe that's why VW didn't set it up like that. It was also possible incidentally to mod the springs further and get 5.5krpm or so out of the engine.
But what's in a number? Why is 4,000 worse than 6,000 if the gears are longer, so it gets you from say 30-70 in the same time, and if the output curve rises in a similar way?
A big petrol engine could well be lovely to drive.. but they drink fuel. If you care nothing for efficiency, waste, pollution etc etc then knock yourself out.
To me, efficiency is a fundamental engineering principle, so a car that does 25-30mpg is just wrong.
