Page 1 of 4

improving fuel efficiency

Posted: Thu Nov 14, 2013 2:47 pm
by Giselle
Any thoughts/tips on how to save fuel? Usually weight saving is a quick and easy solution, but I dunno if the mx-5 has much weight to shed. I'm not sure if much can be done for aero either

I have an auto. Does anyone have advice on how to save fuel in auto??

Presumably a megasquirt could be used to detune a bit, but the cost would probably outweigh the savings.

Anyone? Are there any inefficiencies in the stock motor?

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 3:04 pm
by lizard
Leave the MX in the garage and catch a bus :wink:

In all seriousness just work out what you need to spend on mods to how much petrol that would buy .



My only tip .Its more fuel efficient to run with the roof up and air on .

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 3:32 pm
by 22Silver
NA6 came in auto...?

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 3:33 pm
by hks_kansei
lizard wrote: My only tip .Its more fuel efficient to run with the roof up and air on .


depends.

Air con adds drag at a fairly even level no matter the road speed, where aerodynamic drag increases with speed.
So at low speeds around town it's better economically to have the windows down, at highway speeds better to run the aircon.

Windows up and a/c off is better than both.



As for the original question, don't bother with aftermarket computers etc, the cost will take many years to pay off in fuel savings.
apart from the usual driving style changes you could look into a taller differential ratio, but this will only help once rolling (fuel use may increase during acceleration as the engine works harder to accelerate the car)

also look at the car owned by "Miles" on the forum, he had his NA converted to run on LPG.

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 3:44 pm
by Tumbles
Giselle wrote:Any thoughts/tips on how to save fuel? Usually weight saving is a quick and easy solution, but I dunno if the mx-5 has much weight to shed. I'm not sure if much can be done for aero either

I have an auto. Does anyone have advice on how to save fuel in auto??

Presumably a megasquirt could be used to detune a bit, but the cost would probably outweigh the savings.

Anyone? Are there any inefficiencies in the stock motor?


It's bad because the best advice to save fuel is easy on the throttle, but that would defeat the point of an MX-5.

Servicing the car with a fuel filter at the intervals specified would help, along with the regular oil and filter servicing and air filter. Check oxygen sensors and spark plugs, etc.

Weight saving? You could probably start tearing out the interior carpet and fittings, remove the passenger seat and so on, but you would probably be defected the next time you interact with the police. Best weight savings are made in unsprung weight, 6UL/RFP1 wheels work well to cut that down.

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 3:49 pm
by Mr nanotech
Walk.

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 4:06 pm
by markwid
Over-thinking is bad for you!

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 4:13 pm
by PaulF
What kind of fuel consumption are you getting at the moment? MX5's are pretty good on fuel.

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 5:06 pm
by project.r.racing
worried about fuel usage in a mx5. buy a hybrid.

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 6:30 pm
by Giselle
PaulF wrote:What kind of fuel consumption are you getting at the moment? MX5's are pretty good on fuel.


0 litres per zero kilometres. She's yet to leave the driveway since being towed there :) Will probably finally register her soon though, having finally found someone willing to teach me to drive.
Tumbles wrote:
It's bad because the best advice to save fuel is easy on the throttle, but that would defeat the point of an MX-5.

Servicing the car with a fuel filter at the intervals specified would help, along with the regular oil and filter servicing and air filter. Check oxygen sensors and spark plugs, etc.

Weight saving? You could probably start tearing out the interior carpet and fittings, remove the passenger seat and so on, but you would probably be defected the next time you interact with the police. Best weight savings are made in unsprung weight, 6UL/RFP1 wheels work well to cut that down.


Thanks.

No one beleives it, but I don't intend to drive fast anyway. I'm a really small girl so I just wanted a nice small sexy car that I can enjoy driving. I wanted an MG for ages, but figured going Japanese will be way more sensible for my first car.

I'm trying to stay dead stock, so the carpet will be staying in :) Advice like filters, spark plugs etc is helpful though :) that's what's the type of stuff I was hoping to hear, rather than being told to buy another car, catch a bus or walk

22Silver wrote:NA6 came in auto...?


It's a JDM V-special that has been completely spec'd out so maybe that's why

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 9:42 pm
by emily_mx5
yeah you could get autos in japan, thus the only autos here are imports.
I don't think you should worry, the mx is very cheap to run.

Re: improving fuel efficiency

Posted: Thu Nov 14, 2013 10:23 pm
by NitroDann
The very best advice is going to be to make sure it;s completely well looked after.

I will give you a quick list of things to stay on top of.

Always use good quality fuel.

Clean air filter.

Synthetic oil (doesnt have to be 80 bucks a bottle mobil 1).

Fresh spark plugs, dont spend 100 bucks on a set of platinum or iridium, just good fresh regular NGK ones.

New oxygen sensor (very cheap online and VERY easy to replace also)

AND importantly.... Always make sure the tyres are pumped up, check them at least once a week.

The bonus for all of this is that it will make the car drive really nice, start and run great, and it will keep the steering nice and light and responsive. :)

Happy motoring !

Dann

Re: improving fuel efficiency

Posted: Fri Nov 15, 2013 12:11 am
by Tumbles
NitroDann wrote:AND importantly.... Always make sure the tyres are pumped up, check them at least once a week.


I knew I was missing something!


Giselle wrote:
Tumbles wrote:
It's bad because the best advice to save fuel is easy on the throttle, but that would defeat the point of an MX-5.

Servicing the car with a fuel filter at the intervals specified would help, along with the regular oil and filter servicing and air filter. Check oxygen sensors and spark plugs, etc.

Weight saving? You could probably start tearing out the interior carpet and fittings, remove the passenger seat and so on, but you would probably be defected the next time you interact with the police. Best weight savings are made in unsprung weight, 6UL/RFP1 wheels work well to cut that down.


Thanks.

No one beleives it, but I don't intend to drive fast anyway. I'm a really small girl so I just wanted a nice small sexy car that I can enjoy driving. I wanted an MG for ages, but figured going Japanese will be way more sensible for my first car.

I'm trying to stay dead stock, so the carpet will be staying in :) Advice like filters, spark plugs etc is helpful though :) that's what's the type of stuff I was hoping to hear, rather than being told to buy another car, catch a bus or walk



It's hard to go truly fast in an NA four cylinder 1.6L engine, even if it is only 930kg or so. However, it's still easy to have fun in the Eunos Roadster without going too fast, so you made the right choice.

Not sure if the 1990 came in BRG, but it looks pretty close to an MG if you end up getting wire wheels. I always get asked about it being some sort of British roadster. Much more reliable and easier/cheaper to run though. Best of both worlds.

Towing doesn't sound too good. Get on to fixing it up and enjoy driving it!

Re: improving fuel efficiency

Posted: Fri Nov 15, 2013 12:19 am
by NitroDann
Tumbles wrote:It's hard to go truly fast in an NA four cylinder 1.6L engine, even if it is only 930kg or so.


No way, a stock B16 motor in an NA would be an extremely quick car. But the stock engine isn;t amazing without boost.

Dann

Re: improving fuel efficiency

Posted: Fri Nov 15, 2013 12:34 am
by Okibi
I think once you start driving your MX-5 you're realise that the enjoyment of driving is far more important than trying to save a few litres of fuel.