>As for the throttle plate, it was determined that fuel use dropped
>when drivers adopted a driving technique in which they used lots of
>throttle opening but shifted very early, say at 2000--2200 RPM. The
>other extreme, using shallow throttle positions but keeping it wound
>out higher, invoked far worse fuel economy because of internal friction
>and cycles per unit of travel. But surprisingly, one of the main
>sources of the internal friction was the pumping loss that occurred
>when the pistons tried to pull air past a barely-cracked throttle
>butterfly.
The above points to the main(?) reasons that diesel (cough!!!) engines
are more 'economical' than petrol on a per gallon basis:
1) a diesel engine is not throttled - no pumping losses,
2) a gallon of diesel has 10% (?) more energy content than a gallon of
petrol.
This also means that a diesel engine is only worth having if the car
is driven 'relatively' sedately, i.e. at small 'throttle' openings.
The future is petrol!
Get a computer to control the throttle together with a continually variable
transmission (CVT) giving a range of say 5 mph/1000 revs to 60 mph/1000
revs. This will allow the engine to run at full throttle all the time, with
the computer varying the gearing to suit the speed/acceleration needed.
I hear that 2 strokes (with valves, fuel injection and compressed air
injection?) will also be the order of the day!
Re: the Land Rover Defender (new version)
At last the marketing guys(?) have got their say; a LR not specifically
targeted at the quasi-military sector (in UK) but more towards the 'fun'
side of things. Could it be that they have seen the fun people are having
in old LRs stripped to the minimum (no windscreens in most cases -
determined fun lovers!).
My dream scenario: a full set of Rover V8 vehicles
1) new LR Defender (with 'fun' pack),
2) LR Discovery (for the winter),
3) renovated Rover SD1 Vitesse with 4.2 litre FI engine,
4) TR8 (4.2 litre).
I have made a start - TR7 V8 (3.5).
Regards,
Mike.
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