Posted by Coyoteboy on May 3, 2006, 8:29 pm
> 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.
Still dont see it, my friend has a commonrail TD and gets 45 doing city
driving, which is still above a hybrid?
> 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.
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
Posted by perfb on May 3, 2006, 10:05 pm
"my friend has a commonrail TD and gets 45 doing city driving"
interesting, what make model car is that?
Posted by Michael Pardee on May 4, 2006, 1:54 am
>> 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.
> Still dont see it, my friend has a commonrail TD and gets 45 doing city
> driving, which is still above a hybrid?
We get mid/upper 40s in our hybrid around this hilly mountain town even with
short trips and cold weather. In Phoenix it is consistently over 50 mpg in
town, running A/C in a car that carries 5 adults easily and has what is
effectively a perfectly smooth automatic transmission. Sitting at lights it
is dead quiet most of the time and on the road it's still on the quiet side
of average. In all states in the US it has the SULEV emissions rating. The
merging capability is better than any of our other cars, including our 1985
turbo Volvo (gotta hate that turbo lag!) Ours is the older, less efficient
version - and represents a technology in its infancy.
I give diesel its due: it has undeniable advantages as an auto fuel.
Mike
Posted by richard schumacher on May 4, 2006, 3:21 am
> > 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.
>
> 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.
No, it would be done the way the Prius does it: spin the engine up to
speed before applying compression (that is, hold the valves open) and
fuel.
Posted by Peter Chant on May 4, 2006, 9:20 pm
richard schumacher wrote:
> No, it would be done the way the Prius does it: spin the engine up to
> speed before applying compression (that is, hold the valves open) and
> fuel.
So it has valve lifters. Is the only reason this is not done on regular
engines the extra complexity?
--
http://www.petezilla.co.uk
> 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.