Whilst the media is filled with people claiming that a hybrid is the way forwards (America) or that a small car with no luxuries is the only possible way (various pressure groups), it amazes me as an engineer that very little effort is put into exposing just how much more we can get without going very far off the beaten track and certainly without adding huge complex systems of hybridisation to a vehicle.

Certainly a primary concern is going to be saving weight, and we can do that very easily by using Aluminium albeit at a cost compared to using Steels. This is of course consequence that few people are willing to pay for in comparison, because ultimately the bottom line matters to anyone, however a premium of £1000-1500 for car can be shown to work when the return is great enough e.g. diesel engines currently command this kind of premium in many cases.

What I'm more interested in though is the ways in which the engine itself can be made more efficient. The first one is really simple, downsizing and turbocharging to capture waste energy from the exhaust and we're seeing this happen at the moment, but we could happily take it further than this. The heat coming out of the exhaust isn't all consumed going through the turbo (though it would be nice if it were - turbines/turbos work using a delta in temperature across them to harness power). That low grade heat that is left is of a similar value to that discharged by the cooling system, not really hot enough to do useful work but of significant cost anyway. BMW made a demonstrator a couple of years back that captured exhaust heat to add extra power, and there's no reason why we couldn't do this to generate electricity or even run the air conditioning system. This works more or less the same as a kerosene fridge and would remove significant loads from the engine e.g. a Range Rover has a 14kW (19Hp) air conditioning pump and a 100A (say 5Hp) alternator. Now imagine how much less fuel said car would use when not consuming a "base load" of 24Hp before even moving. We should start on the bigger cars too because there is more potential benefit here.

We can do much with gearing too if the motoring press and motorist can get over the idea that they would have to shift down or the transmission would have to shift down to accelerate. This is akin to keeping the revs low and throttle open (most efficient running is generally at 3/4 throttle or so with lowest engine revs that generate the necessary power) whilst cruising.

A good example of what can be achieved in miniature in a car is what we see in CHP power stations. The company I work for, a well know UK aero engine manufacture has installed gas turbines in power stations in Europe where the combined output efficiency is over 94% considering the electrical output and the heating output used in the local area. We already use the heat from the engine to warm our cabins, we could also use it to cool them too.

None of these engine based technologies are new, nor substantially heavier than those being removed (aircon) and nor are they unproven. What they are though is a shift from the norm, and the question is which manufacturers are willing to make the first jump. Personally I hope it's Tata Jaguar/Land Rover because they have the most to gain and the best models to demonstrate on due to their current consumption rates. I suspect it will be BMW however and to be fair to them their efficient dynamics packages should be present on all cars as a licensed technology or manufacturers own derivative.

What ideas do other members have for improving our cars for efficiency? Read more

Dear all,

I have been offered bio diesel (specifically manufactured) to european standard EN14214, for use in my alfa GT.

The company that remapped the ECU specialize in racing diesel cars and they have said there should be no probs.

What do people think about this considering its almost brand new, i intend to renew the fuel filter after using biodiesel for the first time.

The fuel cost 96 pence a litre and will be delivered to my home for free!

Is this too good to be true?

Kush Read more

Ok, the next issue on my uncle's camper van is that it now occasionally jumps out of 5th gear. We are aware that this is a common design fault following a re-design of the gearbox. My uncle has rejected my suggestion of using an elastic bungee on the gear lever when 5th is engaged.
I won't touch gearboxes these days without a manual. We have a good local gearbox specialist. Does it make more sense to fit a recon box or ask the local specialist to repair the box?
Camper vans do my head in. They are built onto cheap chassis that are designed to run up 150,000 miles in 3 years commercially, then be sold for peanuts at auction. However, the campervan fraternity expect them to cope with tiny miles over many years and are then surprised that they deteriorate faster than cars. Read more

In this day & age of rising fuel costs & higher taxation i have decided to modify my car to run on a mixture of hydrogen & diesel its a simple procedure of converting tap water to hydrogen gas then fed into the engine along with your existing fuel whether it be petrol or diesel.
It Improves mpg in town, open road and motorway conditions. With correct tuning, it is possible to double a vehicle's mileage. Obviously not all vehicles, loads and driving conditions will gain the same. But standard figures show that you can expect a
20%-50% improvement in fuel economy,
It can remove carbon deposits and prevent future carbon build up. The engine steam-cleans itself every day. Reduces engine noise noticeably, with a much smoother engine operation and gear changes. Clean up emissions.
It definitely helps if the problem is unburned fuel due to inefficient combustion. MOT testing kits have shown up to a 98% reduction in harmful emissions!
Longer engine life expectancy, especially the pistons, valves, rings and bearings.

Having said all that I phone my Insurance company to tell them of of my plans and they said they would cancel my policy if i went ahead i asked them why but they cuold'nt give me a reason does this mean that all Hydrogen Hybrids are on the road Illegaly
needless to say i'll be phoning around for new insurance.
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My daughter is changing her Corsa Exclusive (Almost 4 years old) for a Fiesta Zetec S (I tried to talk her into a 1.4 but she did not want to know).

Dealer gave her a discount and a very good trade in value for her car - he claimed he could not find hers in in Glass's guide although it is listed on Vauxhall's "value your car". At the time she paid her deposit they were looking for a stock car but if not available the quote was 8-10 weeks for a factory order.

None in stock and Ford have pushed the build date back and the salesman is making noises about reducing the value of her trade in. If it slips too far she will also have to re-tax and MOT. SWMBO wants me to ring and speak to the salesman on daughters behalf to sort this out but I have refused saying we will do this when we go in to finalise paperwork.

The line I intend to take is that they can have the percentage reduction in the Glass price for the car for the 8-10 week period they quoted (currently zero reduction) and anything else is their problem. If it gets heated I want to be where their other potential customers can hear what is being said. If necessary have prepared daughter to ask for her deposit back.

Am I being unreasonable or am I taking the right line. After all they all swear by Glass' Guide don't they!

Read more