klm77
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Diesel Vs Petrol

Thu Mar 03, 2011 2:40 am

Hey all, I just wanted to get some opinions on what you think of diesel/petrol cars and what you prefer.

First before anything some Pros and Cons should be pointed out. Since there are a bunch, I'm just going to point out a few for each of the top of my head.

Diesel

Pros:
Great on fuel economy (Some vehicles such as VW can get up to 1000km on one tank)
Engines are more durable and could last up to 2x longer.
Have greater torque equaling in the ability to tow more weight.

Cons:
Not as powerful as gas.
Can become very smelly if idling for a long time.
They cost more to buy and maintain.
Can annoy people with the tractor like sound the engine makes

Petrol

Pros:
Have more power then diesel cars
Are more environmentally friendly
Quieter compared to a diesel.
Much cheaper to maintain.

Cons:
Not as good on fuel economy

Though some of the cons on the new diesels these days may not apply (Sound for example).

Thoughts?

[Edited 2011-03-02 18:57:45]
 
mham001
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 2:45 am

The durability claim has been greatly mitigated over the years. They are making diesels lighter now with much higher pressures while gas motors have greatly extended their lifespans.
Ford is making a mockery of the torque claims too. Their new gas motors put a diesel to shame.

Anyway, they're all bad. Go electric!
 
Okie
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 2:52 am

Quoting mham001 (Reply 1):
Go electric!

There you go Coal Powered vs Petrol vs Diesel

Okie
 
andz
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 2:53 am

I have been driving a BMW 320d for the last 5 years and I love it. It is smooth, not smelly, not noisy, you get a vague diesel rattle when stationary but on the move you wouldn't know. It has great torque and doesn't feel my bike trailer when I tow it.

Last year I drove a rented Golf 6 2.0 TDi and I was just as impressed. That had a lot more acceleration than my BMW and felt like it had plenty of torque too. I am seriously considering this as my next car.

Quoting klm77 (Thread starter):
Petrol Pros:
Are more environmentally friendly

I disagree. My BMW has lower emissions than the equivalent petrol car and this is reflected in the CO2 tax you pay on a new one.

Quoting klm77 (Thread starter):
Petrol Cons:
Much cheaper to maintain.

Why is this a con?
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mham001
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 2:57 am

Quoting okie (Reply 2):

There you go Coal Powered vs Petrol vs Diesel

Yep, even the dirtiest coal power plant (their number is diminishing) is more efficient than thousands of individual gas and diesel power plants.

[Edited 2011-03-02 18:57:49]
 
klm77
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 2:59 am

Quoting Andz (Reply 3):
I disagree. My BMW has lower emissions than the equivalent petrol car and this is reflected in the CO2 tax you pay on a new one.

Yes and I agree with you, as I had mentioned some of the cons can be argued due to the new technology/quality of diesel fuel nowadays.

My mistake on the Con for petrol :S
 
Kent350787
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 3:24 am

Quoting Andz (Reply 3):
I disagree. My BMW has lower emissions than the equivalent petrol car and this is reflected in the CO2 tax you pay on a new one.

The NOX emissions are still an issue for diesels, but this tends to be ignored with our current CO2 obsession.

I switched from petrol to diesel last year and overall prefer it. Pros: better fuel economy, thumping torque for engine capacity, giving great pulling force from relatively low revs (great on really winding mountain roads!) Cons: 4500rpm redline without that top end zing of a good petrol, DPF clogs up with too much running around town and has to be actively regenerated.
 
CXB77L
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 3:45 am

I've always driven a petrol powered car and will, for now, choose petrol over diesel any time. I agree that diesels uses less fuel than petrol powered cars, but the two things that annoy me are the diesel smell and the rattling noise at idle. For me, those reasons alone are enough for me to choose a petrol car over a diesel car, even if diesels have improved quite a lot over the years.

Here in Australia, diesel fuel is more expensive than petrol, which seems odd when you consider that petrol is far more refined than diesel oil. That puts the final nail in the coffin for diesel cars, as far as I'm concerned. Despite this, though, diesel cars are growing in popularity over here, but nowhere near the popularity it has achieved in Europe, for instance.
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airportugal310
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 3:53 am

Quoting CXB77L (Reply 7):
but the two things that annoy me are the diesel smell and the rattling noise at idle.

The 2010 Ford Fiesta I rented in Europe this past Summer didn't really have any rattling noise in idle. It was a pleasure to drive. However, I know what you mean....that was a new car, on older models...that can certainly be a 'pain'.
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Kent350787
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 3:53 am

Quoting CXB77L (Reply 7):
Here in Australia, diesel fuel is more expensive than petrol

True, but as the diesel is more economical than petrol, your fuel cost will generally be lower (yes, I know diesels generally cost more to purchase here than the equivalent petrol - I'm only talking fuel costs).

No real diesel smell with a DPF equipped diesel, and the rattle at idle is almost gone with the latest common rail diesels.

I'm still loving, loving, loving the torque - V6 torque with 4 cyl fuel consumption!
 
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WildcatYXU
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 4:04 am

Quoting klm77 (Thread starter):
Not as good on fuel economy

While it's true, let me remind you that the comparison isn't always fair, because:

-the diesel engine in the same car is usually the least powerful option
-current small diesel engines are much more technologically advanced than a regular gasoline engine. I don't think is fair to compare a TDI CR engine to a pushrod gasoline engine

So the only fair comparison would be to compare, let's say, VW's TDi CR to VW's TSI or TFSI. The difference in fuel economy isn't so large in this case.

There is another important fact we should remember: the BTU/gallon value of diesel fuel is roughly 10% higher than gasoline's. So the diesel has a natural advantage here.
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Fly2HMO
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 4:05 am

Quoting klm77 (Thread starter):
Not as powerful as gas.

In terms of horsepower, not always. However, in terms of torque, even smaller diesel engines outperform gas/petrol engines in this department by a long shot. What they lack in top speed they more than make up in acceleration and passing performance, a product of their comparatively very high torque.

Quoting klm77 (Thread starter):
Can annoy people with the tractor like sound the engine makes

Hardly the case anymore. On the outside they may sound clunky still but inside they sound just as quiet and I dare say smoother than their gas equivalents in some cases.

Quoting mham001 (Reply 1):
Their new gas motors put a diesel to shame.

I dunno about the other cars, but I just test drove the Fiesta 1.6L Manual, it's pathetic. No usable torque whatsoever, which really disappointed me as on paper the HP/Torque figures seem pretty respectable. I find it ridiculous that they advertise it as "sporty" and "fun to drive" when it isn't at all.

[Edited 2011-03-02 20:07:04]

[Edited 2011-03-02 20:07:25]
 
Springbok747
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 4:10 am

Quoting klm77 (Thread starter):
Can become very smelly if idling for a long time.
They cost more to buy and maintain.
Can annoy people with the tractor like sound the engine makes

Not true. All 3 of our cars are diesels, and none of them make a tractor like sound or anything. I've had my diesel JK Wrangler for 4 years now, and driven close to 130,000 km without any issues. Yes, diesels cost more to buy (the price difference between a petrol and diesel when I bought the car was $4500), but about the same to maintain. I'd say the highest service charge I've ever paid was $950..but thats about the same as servicing a petrol car at 100,000 kms. I easily get over 800 km on one tank of diesel..much more than a petrol V6 powered Wrangler. My dad's ML350 diesel easily goes over 1000 kms on one tank, plus its quite fun to drive..very responsive.

Don't know about the smell part either. I've never had any issues with any of our diesel cars, but then again I've never left any of them idling for a long time. But I do agree..petrol smells a lot nicer than diesel!
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Kent350787
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 4:12 am

Quoting WildcatYXU (Reply 10):
the BTU/gallon value of diesel fuel is roughly 10% higher than gasoline's.

So the 3% fuel cost premium here in Australia def works to diesel's advantage.

There are so many factors at play, it really depends on what you're after. Looking at the current VAG engines, the 1.8 petrol is more powerful than the 2TDiCR - but the diesel has a big torque advantage. You're right that the fuel economy difference is no longer as great.

Really, if torque was similar, I'd be happy to go either way. My car is only sold as a diesel here in Australia, so the choice was made for me - and it's resolved the lack of pulling power out of tight bends that I've hated with every car I've had until now.
 
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WildcatYXU
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 4:14 am

Quoting Fly2HMO (Reply 11):
I dunno about the other cars,

Well, I'd like to test drive a Golf with the 1.4 TFSI, preferably with MT. 170 hp and 177 lbft of torque available between 1500-4500 rpm sounds really interesting.
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shamrock137
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 4:15 am

Quoting WildcatYXU (Reply 10):
-the diesel engine in the same car is usually the least powerful option

While the horsepower is lower, diesel engines usually have much more torque, which makes the difference in performance when it comes to acceleration. Take the BMW 3 series, if you order the diesel with 175 bhp you get 258 lb·ft of torque and a 0-60 time of 7.9 seconds. Comparability, with the 175 bhp petrol engine you get 155 lb·ft of torque and a 0-60 time of 8.1 seconds.
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Kent350787
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 4:54 am

My 103kw diesel has 350Nm of torque, whereas the 118kw petrol has 250Nm (admittedly across a wider rev range). Combined cycle fuel consumption is 5.1l/100km for the diesel and 7.2l/100km for the petrol.
 
mham001
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 5:04 am

Quoting Fly2HMO (Reply 11):

I dunno about the other cars, but I just test drove the Fiesta 1.6L Manual, it's pathetic.

You need to try the EcoBoost lineup.
 
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airportugal310
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 5:28 am

Quoting mham001 (Reply 17):
You need to try the EcoBoost lineup.

I love the yuppie sounding names...EcoBoost? Really?

Just like 'FLEXFUEL' on a Chevy Tahoe (or similar). Sorry, chief, but you are really not fooling anyone.
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MrChips
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 8:13 am

Quoting klm77 (Thread starter):
Can become very smelly if idling for a long time.

Modern diesels have very advanced emissions controls - the acrid burnt diesel smell is largely a thing of the past (unless you're driving a POS Ford Powerstroke).

Quoting klm77 (Thread starter):
Can annoy people with the tractor like sound the engine makes

Again, only pickup trucks are noisy - mostly because the idiots who buy them want to sound like a semi-truck, for some reason. I've driven a BMW 335d, and let me tell you, not only was I blown away by how fast it was, but by how eerily quiet it was inside as well - the 335d is far quieter than its gas-powered sibling, the 335i, at nearly every engine and vehicle speed.
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MasterBean
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 12:01 pm

Get ready everybody for a massive argument that includes loads of random pointless facts stating that something is better than something else because it just is and I said so so there.

Anyhow, a person will buy a car because they want that version, so deciding which is better is a non conclusive thing. I like Caterhams yet some would say they're completely pointless and useless and that might be true. Petrol is good, so is diesel and some people don't care about the mileage or the torque or how much it cost to fill up. They buy the car 'cos it's pink.
 
JJJ
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 12:48 pm

From a purely financial point of view, diesels only make sense if you drive a lot (over 20.000km per year but depending on specific vehicle), there are a few minor ownership cost difference and resale value but overall they cancel each other.

From then onwards, it's all down to personal choice.

People like diesels for the instant kick and tons of torque, people like petrol because want to rev high and petrol smells better.

Me, I prefer the best of both words: a turbocharged petrol 
 
klm77
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 1:14 pm

I know that when I stated that diesels can annoy people with the sound and can become smelly if they idle a long time, I was referring to the older generations of TDI's so I should have mentioned that. My neighbour has a 2000 VW Jetta TDI and when he starts that car you can hear the tractor like sound. If idling for 20 min, it will start to smell. Though of course as many have mentioned, you couldn't even tell with new cars if they are diesel. I was just in a R class Bluetec a week ago, and if the driver didn't tell me the car was diesel, I would've never guessed in a thousand years at how quiet the engine was.
 
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WildcatYXU
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 2:22 pm

Quoting Shamrock137 (Reply 15):
Take the BMW 3 series, if you order the diesel with 175 bhp you get 258 lb·ft of torque and a 0-60 time of 7.9 seconds. Comparability, with the 175 bhp petrol engine you get 155 lb·ft of torque and a 0-60 time of 8.1 seconds.



Would you mind to post a link to those engines? I tried to find them, but BMW Canada lists 2.5 litre straight six as the smallest, at BMW USA it's the 2.8 litre straight six...
BMW's German site doesn't list a 175 hp diesel (or petrol for that matter). The only models with same power in diesel and petrol version are the 318i and 318d. Both rated at 143 PS, no torque listed. I couldn't find the technical data, but I strongly suspect that we're comparing a DI turbodiesel with a naturally aspirated gasoline engine with indirect fuel injection. The price difference between the two (2650 Teuro) supports this. So, apples to oranges again.

Quoting Kent350787 (Reply 13):
So the 3% fuel cost premium here in Australia def works to diesel's advantage.



The price premium for diesel would be probably larger, but it's offset by different taxation. Heck, in many countries diesel is cheaper because of the huge difference in excise tax. The largest difference I've ever seen was in France in 1995; 4 FFr/litre compared to 5.60 FFr/litre.

I have a feeling that this price difference was a driving force behind development of really useful diesel engines. Small diesels were around since forever, however they were nothing to write home about (who ever tried to cross the Brenner Pass in VW Caddy equipped with a classic diesel engine knows what I'm talking about). The TDi from VW and similar designs from other manufacturers changed everything.

Gasoline is making a come-back as Mitsubishi's GDI was developed by VW (and others) into a brilliant engine concept that is becoming mainstream now.
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mham001
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 5:37 pm

Quoting airportugal310 (Reply 18):
I love the yuppie sounding names...EcoBoost? Really?

Just like 'FLEXFUEL' on a Chevy Tahoe (or similar). Sorry, chief, but you are really not fooling anyone.

I don't need to fool anybody. Chief.

Fact is, gas engine technology has largely caught up to diesel. You might want to check the specs of that Ford Ecoboost 3.5L V-6 they are offering in their trucks, for example before getting snippy. You might learn something. 365 hp with 420 lb.-ft. torque. Or the very soon coming-to-N America I-4 2.0 with 230 bhp (170 kW), and torque of at least 240 lb·ft (325 N·m). Or the latest EcoBoost engine, a turbocharged 1.0-liter three-cylinder direct-injection gasoline unit that returns nearly 60 mpg (US) and emits less than 100 g/km of CO2, set for use in the B-Max.

Chief.

[Edited 2011-03-03 09:38:42]
 
Bongodog1964
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 9:03 pm

I've three diesel engined vehicles, two Fords and one Vauxhall which has a BMW diesel engine. The Ford engines are far superior to the BMW in terms of noise and torque. It has to be said that the BMW engine is ten years old, but one of the Fords is older still.

The most infuriating thing to me is that the BMW has to have the glowplugs warmed up before it will start, whereas the Fords are direct start.

Until I bought a modern turbo diesel, I was of the opinion that diesels were only suitable for tractors, however the modern diesel has none of the smoke, smell, vibration and noise problems of its predecessors
 
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airportugal310
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 9:15 pm

Quoting mham001 (Reply 24):
I don't need to fool anybody. Chief.

Fact is, gas engine technology has largely caught up to diesel. You might want to check the specs of that Ford Ecoboost 3.5L V-6 they are offering in their trucks, for example before getting snippy. You might learn something. 365 hp with 420 lb.-ft. torque. Or the very soon coming-to-N America I-4 2.0 with 230 bhp (170 kW), and torque of at least 240 lb·ft (325 N·m). Or the latest EcoBoost engine, a turbocharged 1.0-liter three-cylinder direct-injection gasoline unit that returns nearly 60 mpg (US) and emits less than 100 g/km of CO2, set for use in the B-Max.

Chief.

Wow...way to COMPLETELY miss the point. Chief.  
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bogota
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RE: Diesel Vs Petrol

Thu Mar 03, 2011 9:29 pm

In my opinion nothing beats the punch of a newer generation diesel engine, and now with the silence of newer generation petrol engines, diesel beat them with their very soft growl similar to the older generation petrol V6. Diesel technology has come a long way and the refinement you find now is impressive.
 
Kent350787
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RE: Diesel Vs Petrol

Fri Mar 04, 2011 2:22 am

Quoting WildcatYXU (Reply 23):
The price premium for diesel would be probably larger, but it's offset by different taxation.

You may be right - I'm not quite sure about them in Australia. I filled up with diesel 20 minutes a go and it was $1.397/l for diesel, $1.369/l for petrol....
 
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airportugal310
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RE: Diesel Vs Petrol

Fri Mar 04, 2011 2:37 am

I'm not completely up to spec on as to why we don't have more diesel automobiles in the US...can someone clue me in?
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cpd
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RE: Diesel Vs Petrol

Fri Mar 04, 2011 2:50 am

Quoting klm77 (Thread starter):
Can annoy people with the tractor like sound the engine makes

Q7 V12 TDI sounds just like a normal V12 engine, and goes like stink! Sounds good too.

But that's what 500hp does, and a modest 4000rpm or so rev range with thumping torque output does.
 
prebennorholm
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RE: Diesel Vs Petrol

Fri Mar 04, 2011 3:29 am

Slightly off topic, the March journal of the Royal Danish Aeroclub brings a test of a Piper PA-28 which had its Lycoming O-320 exchanged with a German Centurion 2.0 engine - a reworked four inline 2.0 liter Mercedes Benz common rail diesel engine. Including reduction gear box (3900 to 2300 rpm at 100% power) and automatic three bladed constant speed propeller

Pros:
Less vibration
Less internal noise
Fits under original cowlings
Very simple preflight check (all electronic, press a button and wait for green light)
- and switch off electric power and see that FADEC continues on emergency battery
Single lever operation (no mixture control)
Low fuel consumption (slightly more than half of the Lycoming)
Cheaper fuel (runs on Jet A1 or road diesel oil)
No carburettor icing possible
Liquid cooled, stable temperature, good cabin heating, no risk of CO poisoning from heating system
Less CO2 emission
Less external noise emission

Cons:
High up front investment, around $50k - more than double compared to a new Lycoming
More complex technology
Reduction gear box currently only rated to 600 hours (Lycoming has no reduction gear)
Engine rated to 1500 hours, expected soon 1800 hours (Lycoming 2000 hours)
"First mover" uncertainty

But this is comparing modern day state of the art technology with 50+ years old technology.

[Edited 2011-03-03 19:38:22]
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Kent350787
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RE: Diesel Vs Petrol

Fri Mar 04, 2011 4:52 am

Quoting airportugal310 (Reply 29):
I'm not completely up to spec on as to why we don't have more diesel automobiles in the US...can someone clue me in?

I've asked the question before and many people suggest it's a perception thing ie. diesels are only for smelly, dirty smoky trucks.

Modern diesels were largely a no-go here as well until the move to low sulphur diesel just a few years ago - I don't know whether this was a US issue as well?
 
JJJ
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RE: Diesel Vs Petrol

Fri Mar 04, 2011 8:11 am

Quoting airportugal310 (Reply 29):
I'm not completely up to spec on as to why we don't have more diesel automobiles in the US...can someone clue me in?

A lof of factors.

For one, Cadillac tried to introduce diesels in the late 70s but the engines were problematic. That created an image that still lingers to this day. Plus there's the different emissions standards in the EU and US (one focusing on CO2, other in Nox and particulates), the generally low quality of diesel fuel in the US until a few years ago, etc.

I've always thought that the US obsession with automatics and diesels are a perfect match, but perceptions take a long, long time to change.
 
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Francoflier
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RE: Diesel Vs Petrol

Fri Mar 04, 2011 12:15 pm

I haven't driven the very last generation diesel engines yet, but I still have a bitter taste from my experience driving the previous ones.

Yes, the torque is high and available at a useable range, yes, they're more economical and yes the power/displacement is now pretty much the same.
But I just couldn't get over how terrible the engine felt. It lacked smoothness, linearity, there was an awful turbo lag which meant you had to drive it at much higher revs than you liked in order to keep the turbo spooled up. The red line comes way too early, meaning that the nice hard acceleration stops rather too soon and you end up shifting too much.
It sounded terrible as well.

I hear the latest generation Euro diesels have improved a lot, but so have gas engines, and when it comes to driving pleasure, nothing will beat them.

If you enjoy driving and cars in general and don't need to drive 30000 kms a year, a gas engine works very well.
For 95% of people for whom a car is just a way of getting there and who favor looks, economy and confort over performance and who change cars relatively often (gas engined cars depreciate faster around here) then diesel all the way.
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bogota
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RE: Diesel Vs Petrol

Fri Mar 04, 2011 12:54 pm

Quoting JJJ (Reply 33):
I've always thought that the US obsession with automatics and diesels are a perfect match, but perceptions take a long, long time to change.


I think the US is a market where perceptions take longer to change, I lived there 20 years ago and I still visit regularly and always hear the same stories regarding problems in certain cars that I heard 20 years earlier when those issues are hardly heard years later. i.e. Jaguars and reliability (JD Power in UK has rated them top in reliability for a few years now) Audi and the breaking issue (Long way from this ever happening) or even the use of smaller efficient petrol engines for larger cars. So my opinion is that the same thing happens with Diesel, it will take more time than in other places to change the image.
 
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garpd
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RE: Diesel Vs Petrol

Sat Mar 05, 2011 10:37 am

I think these days in terms of economy and eco friendlyness, Petrol and Diesel cars are on par with each other.
Fuel economy mostly depends on your driving style these days but the Diesel will usualy deliver 50 to 80 miles more per tank of fuel, depending on what you do with it.

Reliability on properly engineered engines is not an issue these days, petrol or diesel.
I have a Peugeot 406 Coupé with the EW10 2.0 Litre Petrol engine. This engine is solidly built and good for at least 200,000 miles before an overhaul with the correct maintenance. I know, I've done it with my previous Peugeot 406 Saloon.
However, the old perceptions are still very much evident. I've seen Petrol engines cars with 100,000 miles selling on ebay for less than a scrap dealer would give you and alower or similarly equipped Diesel version of the same car going for rediculously high prices.

For example (I was watching two auctions on ebay for a car before I got my coupe):

1999 2.0 Litre Petrol 406 Saloon Executive. 125,000 miles. Full leather interior, electric pack with 6 CD changer, Air Con (functional) and Alloy wheels, full service history. One owner: Sold for £750.

1999 2.0 HDI Diesel 406 Saloon LX, 225,000 miles. Cloth interior, manual windows and seats, Radio/Cassette, no air con, steel wheels and service history to 150,000 miles. 4 owners, ex-Taxi: Sold for £1740

Madness! But the well known and widely used Peugeot HDI Diesel engine will always makes whatever car it is fitted to more expensive to buy, even second or third hand, than an equally equipped petrol model, sometime even a higher equipped model like my example above.. This eats away at any fuel economy gain.
Diesel is almost 10pence a litre more expensive than Petrol in the UK. So any advantage of economy is as goond as erased at the fuel pump!

Noise? Well, modern diesels are very quiet.
I drove a Ford Mondeo TDCI Titanium last month. In the front is a Peugeot HDI 2.0 Diesel engine.
It was faster than my Coupé ever could be, utterly luxurious to be in and even quieter than my Coupé when idling, driving around town and on the motorway. Sure you could hear the rattle of the tractor engine when you gave the engine a quick snort of the pedal, but I kid you not when I say it was 90% quieter than the Mondeo Diesel hire car I drove 8 years ago.

Diesel v Petrol is down to personal taste. I cannot see any clear winner in either camp.
They both have pros and cons and these days both cost a fortune to buy, run, insure and maintain.

Would I buy a modern diesel? If I could afford a new one, yes. But I would equally buy a petrol too. Both cost about the same these days.
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GST
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RE: Diesel Vs Petrol

Sat Mar 05, 2011 11:13 am

Considering at this is an aviation forum, I'm shocked that no one has picked out the obvious (or maybe they have but I didn't register)...You can put Jet A into diesel cars and run with pretty much identical mpg, and with lovely smelling exhaust fumes. As there are fewer impurities in Jet A to lubricate, you either have to add a bit of two stroke or fill up with normal diesel every fourth time or something to stop the fuel pumps getting worn. Jet A is cheap as chips compared to petrol or diesel in many countries!

No idea if it results in fewer particles in the exhaust though, would be nice since those are a massive killer (or contributing factor to early death) of people living next to busy roads.
 
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garpd
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RE: Diesel Vs Petrol

Sat Mar 05, 2011 12:38 pm

Quoting GST (Reply 37):
Jet A is cheap as chips compared to petrol or diesel in many countries!

And also illegal to use in cars. If the police are behind you and smell it, you're likely to get a huge fine, the customs and excise van towing your car away, and possible a court appearance depending on how long you've been using it.
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GST
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RE: Diesel Vs Petrol

Sat Mar 05, 2011 2:12 pm

Quoting Garpd (Reply 38):

And also illegal to use in cars.

Here in the UK maybe, but not everywhere.
 
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RayChuang
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RE: Diesel Vs Petrol

Sun Mar 06, 2011 3:50 am

While diesel engines have pretty much overcome their "no high end power" and engine clatter issues, they still haven't completely overcome the problems of diesel exhaust, namely higher NOx output and diesel particulates. We can reduce NOx and diesel particulates, but the exhaust emission controls necessary to do this are VERY expensive and will offset the lower fuel consumption advantages of a diesel engine.

Besides, gasoline engines have gotten a lot more fuel efficient lately, thanks to new technologies such as direct fuel injection and variable valve timing on both the intake and exhaust sides. Indeed, the 1.6-liter I-4 Hyundai Gamma engine with these features generates 138 bhp (103 kW) of power, a very impressive feat for such a small-displacement engine. And the engine is very fuel-efficient, too.
 
bogota
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RE: Diesel Vs Petrol

Sun Mar 06, 2011 5:14 am

Interesting point of view as my understanding is that new diesel technology is more enviromentally cleaner than petrol technology. That is if your country has clean technology diesel.

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