Building for efficiency instead of performance

[Greenbeast]

I'm wondering about the Roadster as a platform for an ultra-efficient petrol car or all electric vehicle.

I currently drive a citroen c1 which can do 70mpg+ (extra-urban).
I was wondering about the possibility of putting one of these engines in the roadster to gain even more mpg.

Thoughts anyone??

[Talonmotorsport]

I have supplied a few chassis to a training centre who have put 2 very large electric motors running through a type 9 in to a tiger chassis. The only problem is that for every 5 miles of driving you need to carry a 5kg battery which takes 12 hours to charge. Have you considered using a small NA diesel with a turbo? Don't use a turbo diesel just a NA with an added turbo, this means it has smaller injectors so good for economy but burns the fuel more efficiently. You could always get one of those under car mounted speaker sytems so that you can mask the diesel rattle

[Greenbeast]

I've done a bit of research into the electric side of thing, and i may go that way.

What do you think about the ease of fitting a different, much smaller engine in?
I like my little c1, it's quite perky round town and can handle the motorway with ease, fitting it's engine into something that weighs 2/3 as much should improve acceleration but also overall efficiency, no?

[twinturbo]

I would find an efficient Oil Burner, or try LPG + Petrol.

Electric vehicles just shift where the energy is created, it's often created by power stations that waste fuel as they can't produce on demand efficiently. The Batteries cost a lot to make, transport and to dispose of. Add to that the total in-convenience of having to find a charging point and they realy make little sense.

Even a relativly old VW 1.9TD will probably see into 60-70's if driven conservativly in a roadster. You may have to calculate so gearing ratios to keep the engine at it's optimum.

TT

[Greenbeast]

I'm comfortable with the downsides of all-electric, i'm weighing up the options.

Where i'm not sure is the donor engine business. I already see 60-70mpg with my current petrol, surely i must be able to easily beat that in a roadster?
What potential pitfalls might i see using a unusual donor engine/drive train?

[twinturbo]

Gearbox is the usual sticking point, otherwise we would have all sorts of tasty engines in frequent use.

And Complex Imobalised Engine management systems.

TT

[Greenbeast]

I'm gonna really show my ignorance here but how come you can't just use the original gearbox?

[voodoo]

Most modern cars have transverse mounted boxes as they are FWD, the roadster has RWD.

Personally I have been looking at the feasability of running a NA diesel on Biofuel, in addition we are working with a local company that has developed a biodegradable alternative to GRP. Strengthwise it is better, costwise it can't get close.

Matt

[AshG]

personally i think your wasting your time. the roadster has the aerodynamics of a brick. the best way to gain efficiency is to move the car through the air more efficiently.

typically a 2.0 zetec will do between 35-40mpg in something like a focus. have you ever asked yourself why it still only does 35-40mpg in a 7 which is less than half the weight of a focus?

[Greenbeast]

Voodoo, thanks for that, knew it'd be something obvious.

Ash, good point