The original poster never said anything about tire size, only wheel
size. A smaller wheel will take a narrower, higher profile tire. A
narrow tire translates to less rolling resistance, and therefore
better fuel economy. Increasing tire pressure can also cut rolling
resistance, but can increase tread wear (in the center of the tire)
and decrease handling.

There are lots of things that can be done to improve fuel economy
such as lowering ride height, putting skirts on the rear wheels,
filling body seams, taping off openings into the hood, fitting a sleek
pan underneath the car and so on, but they are not practical in the
sense of giving you a return on your investment. If the objective is
to treat this as a hobby, or a science experiment, you can have
lots of fun.

Dan

(This account is not used for email.)


bootch (bootch@nc.rr.com) writes:
> abc <a@bc.net> wrote in message news:<87jpj05t9k1v4ais4b5kdl6s7hhf0c9okb@4ax.com>. ..
>> i'm trying to improve the fuel economy on my 95 civic coupe auto by
>> changing to smaller tyres. best i can get is 36mpg with stock 15"
>> alloys. I need to get at least 40mpg if possible. I was wondering if
>> anyone knows if 13" or 14" alloys would fit. I think these were
>> standard on the hatchback models. Thanks
>
>
> Yes, smaller wheels would make the odometer show greater than one mile
> over a one mile measured course. So you it would appear that you were
> getting better mpg.
>
> In fact, you might get real better gas mileage if you went to larger
> wheels. They would make your engine rpm's slower to go the same real
> speed (again, your speedometer/odometer would be incorrect), and the
> engine might run more economically at lower rpms. But if you have a
> manual transmission, you might be able to run at lower rpms without
> changing wheels.
>
> Your best bets is to change your driving habits: conserve momentum,
> brake as easily as you safely can, accelerate slowly. Pretend you're
> a limo driver and are concerned about the comfort of your passengers.
> Be at one with the calm and serenity of your Honda.
>
> To answer about wheels, some of the old CRX's had 13" alloy wheels,
> but not in the more modern styles. They might not fit over the brakes
> if the brakes are bigger on the Honda's with larger wheels.