Identical servicing intervals was devised by the marketing guys. Any interval is ok as long as it gets through warranty. But the fuel, and the high compression, and effective compression at idle means lots of carbon gets into the oil fast! Synthetic or otherwise does not stop this. If you want your engine to last change the oil when its looking dark. Carbon is abrasive. That means every few thousand miles unfortunately.
But they have LESS torque not more. They feel this way simply because there is no revs or power!
Yes but i just see carbonising oil, worn pistons and cranks!
No, the popular engines before the ones you mention below were indirect injection (eg XUD).
(Just in case there's confusion, I'm not comparing with petrol fuel injection, which is typically even more indirect (as in, outside the cylinder). Indirect injection on a diesel means it goes into a swirl chamber first.)
And those two engines were both direct injection when the competitors were indirect.
Erm, I don't think he was claiming his diesel was "better" than a 1-year-old Merc diesel (I'm guessing a CDI).
To be honest though, direct injection's been around ages - turbocharged direct injection dervs have been around since the first VAG TDIs (5-pot 2.5 and 4-pot 1.9), and a PSA 2.5TDI in the XM a bit before that, possibly, not forgetting the Perkins 2.0TD which had direct injection.
Out of those, I think it was only the VAG ones that had electronic injection, and were a massive step forward in terms of derv engine technology. Since then (1991 - that's nearly 15 years ago), all they've really done is put more turbos on, strengthen things a bit, increase boost, and run the fuel at insane pressures. The basic technology of most, if not all, modern diesels, has been there since 1991.
Modern "performance" diesels when driven hard really won't be that much more economical than a lot of modern petrols, and when driven gently they'll do fairly well, but then, so will modern petrols (as in Ronny's example). Though due to their nature, diesels will always be more economical on shorter journeys and whilst idling.
The earlier crop of modern diesels i.e. the early VAG TDIs, will return extremely impressive mpg figures, thrashed or not.
I was more talking with regard to the more recent developments of the last 5 years or so
Precisely. That was my point. That those engines were ahead of their time in a lot of respects, and are basically, bar higher boost and fuel pressure, the basis of virtually all modern diesels.
Insane pressures are to atomise the fuel better giving little gain in performance but some emmision gains and minute economy improvement as all the hydrocarbons get burned.
They dont make much difference to you or I driving it though...
I've had stuff that on paper should be the best thing since sliced bread to drive, which I've hated, and other stuff which by rights shouldn't be appealing, and is in the flesh - Ford made a living out of selling such s**te in the 80's ;-)
I'm not going to keep arguing the toss, if you cannot absorb what I've said - I'll state it more clearly for you here.
I've had lots and lots of cars, petrol and diesel.
I liked some of *both*, and found weaknesses and strengths in *all* of them.
For my daily driver, I prefer a decent, well engineered modern diesel, having had plenty of both - I liked my Golf TDI, and I want another one, if not that one, back in the fold soon.
When I want to get my kicks, I take my petrol powered bike out.
When I want to ferry my kids about, do the shopping, go on holiday etc., I'm not that fussed about arm wrenching performance etc. I like decent economy, and a car that doesn't struggle when it comes to a hill, and a modern TDI does this all with ease.
I like the way diesels tend to be more relaxing to drive round town, due to the torque and invariably larger clutch making for something that will glide off the mark with hardly any throttle, if any.
Yes, I could have an auto for the same effect, and in terms of the size of car I tend to favour, I'd end up with something more likely to break expensively, and which won't get anywhere near my nice manual TD, in terms of economy.
I'm not going to argue these points again, so take the above as my 'given', when it comes to why you're wasting your time trying to convince me I need a petrol again - I've had several lately (given I trade in the odd car), none of which came close to said Golf for economy.
And none that were any quicker in the real world really, either.
I ask you to look above again - you said yourself you posted because you're specifically fecked off with one vehicle which compelled you to post, yet your post was apparently aimed at all diesels.
Yes, well have you considered that a Ducato diesel isn't the pinnacle of diesel technology, and that Fiat, especially in that context, were never that well made or resilient???
You're blatantly drawing your conclusions and opinions, from this experience.
Ok... so fit the same to your petrol... and then compare the relative economy achieved by it vs the diesel then.
LOL
Not slightly.
Buy the right car, and you gain by a lot.
I've *proven* this for myself - I used to be a courier... I've done enough miles in both, to know which one cost more to run, than the other, whether we're talking long runs, or stop start around town.
Yes, you keep mentioning this... see below.
I hate to tell you this... but if you buy the right ones... the engine lasts for over 200k without any bother at all normally, so long as it's serviced on time.
You *are* therefore, talking illconsidered bollocks on this one, not least in terms of how 'gutless' they tend to be.
Go look on Autotrader / eBay etc., if you don't believe me - loads of leggy diesels on there, all in quite good mechanical shape.
That, and I don't tend to buy new, so your last point is pretty irrelevant.
And uses more fuel... a lot more fuel over the best of the TDI bunch, and costs more to tax.
Oh that's easy, diesels are s**te, end of story. Now can we talk about cars rather than than paupermobiles for people who think more about MPG than what a car is actually like to drive?
Add, impossible to modify for performance, for any real value of the words "modify" and "performance'.
With the s**te rev range of a diesel, the way it comes off the shelf is about as good as it will ever be. Get a big, lazy Yank V(6,8,10) petrol engine and you can turn it into some sort of monster.
Diesels are for the Reginald Molehusbands of this world.
Yup, I keep getting people telling me that diesels have changed and that all the drawbacks ahve disappeared. The BMW diesels get cited as examples of how good they are.
Yet whenever I follow one, it chucks out black smoke, even if th eplate says it's less than six months old. They all rattle like a bag of nails, the rev range is laughable, and no driver seems to be able to get any "go" out them despite claiming that they go like stink.
Oh yeh and the drivers of disels all seem to have massive chips on their shoulders, judging by the number of times I get tailgated by Audi/Passat
1.9Tdi drivers. Here's a clue chaps, I'll drop back to the left after I've overtaken the car to my left. And no matter what you think, your car can't accelerate as fast as a 4.2 V8 supercharged petrol engined car. The reason I'm not screaming up the motorway with my engine at
4,500 rpm is that I don't need to, not because I can't. Besides, 155mph is a tad illegal in British motorways.
Inital cost and servicing costs are't much different on the used market. Service intervals are pretty much the same these days. So I'm disregarding that one :)
2) Diesel engines are all Turbocharged.
3) So they make more torque than their equivalent NA petrol engines.
4) So they're a nicer drive because of that, and because you don't have to rev them to make good progress.
Only a little.
Yep.
Nope. 200bhp of Diesel power will offer almost identical real-world performance to 200bhp of Petrol power. Infact, if we really are talking real-world performance, then the Diesel will be quicker.
No, because that would cost a huge amount of money ! And then even more to insure it. And then the petrol engine would use even MORE fuel !
The Turbo on a Diesel is free (unless you buy brand-new) - it's already there right from the word go.
The Turbocharged petrol engines that you refer to (the ones which make lots more power) cost lots more money.
If you want your Turbocharged Petrol engine to cost a similar amount to the Diesel, and offer some sort of economy, it has to be a low-blow setup, like VAG's 150bhp lump. But then it's no better than a Diesel !
They're all Turbo'd. So they make MORE torque size-for-size.
Per what ?
Diesels make MORE power per litre of fuel consumed.
They make less power per purchase-cost.
Only at idle. And you can't hear that from inside the car anyway.
No. They're a nicer drive, because they're all Turbocharged, so they make lots of nice torque. See above.
No. That's a none-thing. If you didn't like the engine-braking, then you wouldn't be using it :)
That's a none thing. Petrol stinks just as much anyway !
That's a none thing. Don't be clumsy :)
Except that they don't wear faster. Modern Diesel engines last just as long as modern Petrol engines.
Starters and Batteries are built bigger to cope. But they cost more to replace for the same reason.
Except you can just leave it in 5th/6th once you've got going and it'll be quite happy, even overtaking.
That's a none thing. And you can't hear it from the inside.
I like them :)
Not any more.
To conclude :
The only real advantage I see to a Petrol car, is the purchase price.
I could change my petrol car tomorrow for a Diesel, and I could get a faster, more powerful, more economical car, with a nicer drive. But it would cost me lots.
Or I could swap it for another Petrol car, and I could get a faster, more powerful car. But it would be LESS economical. But it would be cheaper :)
You're right that today's Diesels are expensive enough to wipe out the fuel-economy gain. That's why I don't own one :(
3) I could drive my 205 TD with water coming over the bonnet without any ill effects which was useful. But then again, with a bit of preperation I could do that in my petrol XS too.
Having driven an old style TD in a vaguely competitive manner I found it to actually be quite good. With 80ish bhp isnt wasnt lightening quick but once you got going it was pretty good. I won a road rally in the white TD and a guy that couldnt keep up in a rover 416GTi remarked at the end 'those
1.6GTis are quick arent they?' He was a bit shocked when I told him what it actually was!
Not quite so far behind as you're making out. Hence the new Alfa JTDs putting out 200bhp.
(OK, so you could push more out of a 2.4 petrol with a turbo - but then the economy would be s**te - if you gave both 200bhp, the diesel would slaughter the economy of the petrol anyway)
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