40 mpg Prius vs 50 mpg European Diesel cars

That makes sense - I assume the clatter is from the mechanical injectors.

Mike

 

When I was on The Big Rez (the Navajo reservation that covers much of
Northern AZ and part of New Mexico) in November, I paid nearly $.90 per
gallon more for diesel than the regular cost. I guess it is because the
locals don't use diesel.

Mike

 

In our older (2002) version, we get mid/upper 40s around town, although good
weather pushes it over 50. It also gets around 50 at 65 mph, but drops to
the very low 40s (depending on load) at 75 mph. Air resistance, for sure.
The current version is supposed to do better at least in town, dunno about
the highway.

Mike

 

Modern diesels have electronic fuel injection. Here are some good
descriptions of what causes diesel clatter:
http://www.eng-tips.com/viewthread.cfm?qid=139341&page=7

 

That's an interesting link, although about all I can say is the subject of
clatter is still controversial. It sure sounds like the combustion profile
is important.

Mike

 

I wouldn't describe the subject of the source of diesel clatter as
controversial. IMO, "uninformed" is a more accurate description, especially
in the U.S. where diesels are not common in passenger car applications.

Basically, diesel "clatter" is the same sound you get when a gasoline engine
is knocking. Add different tolerances and you get more noise at idle.

 

One of the problems in the USA is that our diesel fuel has a lot of
sulfur, which makes for stinky polluting exhauts gases. If and when we
can get low sulfur diesel fuel, the situation could then improve.

Morton

 

Overall mileage. I actually get better mileage on the freeway than I do
on surface streets; that's because my surface street driving usually has
a stop sign every half mile or mile, with speed limits of 40 to 50 MPH,
and usually for fairly short distances, so the engine doesn't get to
warm up. When I'm in downtown traffic with speeds of 25-35 MPH, I often
get in the upper sixties after the first five to ten minutes of driving.

The two people I personally know of who get in the sixties live in West
Virginia and in Hawaii.

 

<snip>

Commonrail diesels are VERY good. Comparable power and better torque
than all but the top end petrol model-mates. They drive less like a
diesel than old TDs and get HUGE economy. Theyre quiet, not quite as
quiet as a petrol I admit, but certainly quieter than an older petrol
engine. This is why ive never seen the point of hybrid as a current
choice of car, maybe in 10 years when theyve matured.

J

 

Because the US uses a dirty blend of diesel fuel. That is scheduled to
change in a year or 2 with a mandate for clean diesel fuel.

 

Because the US uses a dirty blend of diesel fuel. That is scheduled to
change in a year or 2 with a mandate for clean diesel fuel.[/QUOTE]

Ultra-low-sulfur (<= 15 ppm) Diesel fuel becomes mandatory for retail
sale in the US on 1 Oct 2006. It was to be 1 July, but the Bush
Administration, god bless 'em, decided that the poor old oil bidnis
needed some more help.

 

Ultra-low-sulfur (<= 15 ppm) Diesel fuel becomes mandatory for retail
sale in the US on 1 Oct 2006. It was to be 1 July, but the Bush
Administration, god bless 'em, decided that the poor old oil bidnis
needed some more help.[/QUOTE]

Yes, I see the poor b*st*rds made hardly any money this year.



*** ***

 

Hybrids work at the other end of the driving spectrum. The only advantage
they offer on the open road (where diesels shine) is the ability to reduce
engine size while maintaining passing performance, but in town they reduce
the amount of time a gas or diesel engine is run in the lowest efficiency
ranges. Hybridizing with a turbo diesel power plant is a very attractive
idea - each covering the weaknesses of the other. There is no reason a TD
hybrid 5 passenger sedan couldn't offer more than 100 mpg in town and 80 mpg
on the freeway, at least at 65 mph. Mainly it takes advances in the power
electronics.

Mike

 

I think the biggest drawback to a hybrid diesel is cost. Both the diesel
powerplant and hybrid power plant cost more than a conventional gasoline
(etrol) engine so a diesel hybrid would have a double cost disadvantage to
overcome.

 

Hybrids work at the other end of the driving spectrum. The only advantage

Still dont see it, my friend has a commonrail TD and gets 45 doing city
driving, which is still above a hybrid?

Would be harder than with a petrol - re-starting a diesel requires far more
cranking torque, so you'd need more powerful motors and its likely to cause
a jerk, unlike a petrol car that can smoothly be 'bumped' as its low
compression.

J

 

Is there some other factor that overrides the inherent efficiency of

Dont worry, you are getting to pay the extra 5 cents per gallon that the
new hydrotreators are costing. The refiners pay those costs right along
to the consumer.

Lynn

 

"my friend has a commonrail TD and gets 45 doing city driving"

interesting, what make model car is that?

 

Drivel indeed, starting with the 40 mpg Prius bullshit.

 

I get better mileage than that with my Prius, burn less expensive fuel, and
my exhaust emissions are cleaner. What's your point?

 

Trains and heavy trucks are using diesel engines. What does that tell
us?
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