iam7head

Hi gang! in the name of science and quest for higher MPG on the s2k, I am just wondering who's right between the two "methods"? please feel free to share your opinion and comments.

*Let's not lose focus on the topic by arguing "Mile per fun vs gallon", "local law/safety on coasting in neutral", there are great points but it's not the subject of debate here, to leave the variable to minimum, let's just leave all the modifications, light weight and snake oil out of this also

ON a bone stock s2000..

A)Coasting in neutral: lower rpm=less gas being sip=higher MPG(our trusty old gas golden rule)

B)foot off the gas pedal while car in gear: higher rpm(but according to many auto MFG, newer car are smart enough to determine you are coasting and somehow the injectors will stop firing=no gas use despite the higher revs)

C)shifting at low RPM: low rpm, higher gear=less gas usage(I guess the counter point is instead of shifting low, shifting at the motor's RPM "sweet point" or the most efficient operation range save more gas)

There are extensive records and magazine articles on all three of the subjects but what's your experience with those technique on the s2000?

THANKS, THX

iam7head

my personal experience so far

personally never have any luck "C" or shifting extremely low, i am just starting to learn to drive with "B".(I mostly coast in neutral as i approach a light/stop sign.)

My personal best is a hair north of 30mpg, my over all MPG for 2008(yes i kept complete log on mpg/gas receipt) is around 25mpg, about 80 %HWY and 20% local, pretty aggressive driving style.

jyeung528

i've done all your ABC methods to try to increase gas mileage.

my experience is that none of those really work.

what worked for me is to accelerate VERY slowly, and shift at 3.5K. when i reach the coasting speed, i shift to the next higher gear and coast at low rpm. if i need to accelerate, i will downshift, but accelerate VERY slowly.

this shows me that more gas is consumed via acceleration than any method of deceleration can save.

with this method, i was able to achieve 27 mpg in CITY driving. with your methods ABC i only achieved 24 mpg.

gfresh

http://en.wikipedia.org/wiki/Drafting_(racing) which you should not do ever on a public road.

SpitfireS

iam7head Posted on Feb 21 2009, 09:32 AM
Coasting = revs without throttle.
Should be easy to detect by any ECU and IMO they do it.
Coasting without throttle uses 0 fuel.

What about keeping your tires at recommended pressure?
Or slightly above (as long as it doesn't hurt performance too much)

Driving top up (less fun but more fuel efficient)

No airco.

Oh well...
Just get a Honda Insight

skatebrian624

biggest fuel saver is a conservative driving style. coasting while in gear still uses fuel during the deceleration and idle, just relatively less.

s2kswe

The key is to make the engine put out as few horsepower as possible on average. Generally spoken, accelerate slowly, but don't drive fast at all as you are fighting drag from the air that increases by the square of the speed. Use a higher gear whenever the engines rpms allow it, but downshift if it has to "work" (You can easily hear and feel that).

When going downhill, push the clutch or put the neutral (Use the positional energy the car possess from higher ground), on flat ground maintain a comfortable speed, when going uphill accelerate slowly in advance of the hill and let the car drop speed when climbing the hill. Do not use much throttle. Downshift if required. Avoid the engine to "work".

I think this is the most economic driving you can do, its basically about common sense it isn't magic. Fighting drag + friction losses all the time and converting movement energy to positional energy back and forth.

Also remember to take away excessive weight, have the right pressure in the tires etc. Everything helps.

ECale3

While I don't understand why we are having this conversation in relation to an S2000, I will offer a little input.

My personal best mileage was 35.6MPG while using none of those techniques on a highway cruise to Ocean City.

s2kswe

Well the best conditions for a high gas milage is ofcourse a straight road, no stops no breaking and maintained speed. So I guess you had just that.

I can agree with the discussion being quite odd in relation to the s2000. Certainly nothing i practice myself when using my s2000

ECale3

^ Not really. I was having some fun and took some twisty back roads there

It was basically a freak occurance, because I also had the AC on!