On Saturday, 10 March 2018 15:13:47 UTC, NY wrote:
"Dave Plowman (News)" wrote in message
...

If you want a small petrol engine that pulls like a diesel find one with a
turbo or supercharger. It's that which makes the difference.

If you really want to define gutless, think of older small diesels before
turbos became the norm.

True. The very first diesel I drove was a Golf many years ago. It didn't
have much pull. It was no match for my 1.8 petrol Golf.

Bu they've improved to the extent that I'd regard a turbo as an essential
part of a diesel, whereas it's optional on a petrol unless you want ****-hot
acceleration.

But for an even bigger example of gutless... I was loaned a Pug 2008 (the
SUV-wannabe that's based on the 208) by the garage while my car was in for
work. It had a 1.2 3-cylinder engine and it was major effort to get it
moving from rest, and then engine throbbed and barked (yes, that's the best
word to describe the noise it made) as I set off or when I accelerated out
of a roundabout. The engine also ran at about 3,500-4000 rpm at a normal
60-70 mph which made it very noisy.

OK, that was an exception: a heavy car with a *very* underpowered and
therefore high-revving engine. But even a supposedly powerful car can
suffer. Another garage loan car was a petrol Pug 306 with IIRC a 1.8 engine.
Its 0-60 acceleration was superb - to the extent that I had to be careful
not to overcook things when setting off at junctions. But on the motorway it
was painful. It had virtually no 50-70 acceleration (I tried 5th, then 4th,
then 3rd gear) and even in top the engine was screaming away. No match for
my diesel 306 which didn't have quite the 0-60 but had considerably better
50-70 which is where it really matters on a long motorway journey where you
may get stuck behind a slower vehicle and then need to accelerate hard to
get past it when moving into a lane where other cars are wanting to do way
above 70 and you want to overtake and then get back to Lane 2 as fast as
possible.

lot faster than some things I've driven then

I wonder if manufacturers will ever develop a cat which can turn NOx (NO,
NO2) into something less harmful. I think DPFs have reduced the amount of
particulates, but it's the NOx that is the lingering problem for diesels..
I'm not sure what is is about compression-ignition that produces higher NOx
than spark ignition. Maybe its simply that they are very lean burn, whereas
petrol engines are stoichometric - they have an accurate petrol:air ratio
rather than a great excess of air relative to fuel with diesel.

higher burn temp means more of the N2 reacts.


NT