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AltaKnight

AltaKnight

Jedi Knight
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a VW golf 1.9 diesel get 46 mpg in mixed driving.....
when my TR6 gets about 22 mpg with a tailwind?

Just got back from the UK where I had a rental VW golf and that's what it got, that car had lots of get up and go along with it.

ps. I think I know the answer
 
Digging back to the depths of my memory (uni was a while ago!)

First, there's simply more energy available in diesel fuel so you can get more out of a gallon. As for the rest, your TR6 is probably tuned for power not efficiency, and has a carb or three as opposed to direct injection, lots of sensors and a computer or 10.

With the advent of common rail direct injection, diesels stoped being clunky bus engines a few years back, the new ones are definitely quite frisky!

Plus if you're anything like me the right foot gets a little heavier when you're driving the TR :smile:

Cheers
 
Another significant difference is that there is no throttle on a diesel engine, which means greatly reduced pumping losses under cruise conditions. The energy used to compress the intake air (manifold vacuum) to ambient is lost.

This is the main reason (tho by no means the only one) that a small gas engine will get better "cruise" gas mileage than a larger one.
 
It is amazing the fuel consumption you can get out of turbo diesels these days, but really we should be expecting figures like that. My TR3 recently returned 32mpg on a mix of motorways and small country roads. My Honda CR-V struggles to match that. You may say that the Honda is a much larger vehicle, but 50 years have passed and both are 2-litre petrol engines. I don't really think that is progress.
Don't forget that your TR6 is filled up with US gallons, so you would get more out of a UK gallon!
 
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