He's right to a point. At some speed, friction negates the mpg increase from going faster.

 

There was a thread here where people were arguing about what speed gives the best fuel economy. Many people reported experiencing a higher fuel economy at 80mph than at 55mph. Someone was going to set up an experiment, but I don't know if it ever happened. I'd try to dig up the old thread, but I'm too lazy.

 

I get better gas mileage going 80mph than 75mph...but that doesn't mean I do it on a regular basis, only when going on very long trips.

 

The best gas mileage is achieve between 35-55mph. Basically cruising at the lowest RPM in the highest gear without lugging the engine. Air resistance increases with the square of the velocity, so if you double your speed you have ~4 times the air resistance fighting you...

Basically picturing the right side of a parabola with the x axis being time, the air resistance increases very quickly...

His statement applies only to low speeds (<~30mph) Some cars cannot cruise at this speed without lugging the engine, therefore having to be in let's say 4th instead of top gear (5th) You get worse MPG in 4th at 30mph than in 5th at 35mph, see what I am getting at?

 

Am I shifting too late or something? I only get 210mph out of a full tank for city driving.

 

What about 65mph vs 80mph?

 

I'd say so. Keep your shift points below 4000 and see what your MPG is then... iirc the S2000 gas tank is like 13gallons... so that'd give you like 16mpg with your 210 mile figure... I'd venture to say that you enter VTEC a bit too many times during your daily commute... Nothing wrong with that, you're just not going to get higher than 20mpg

 

ok, although I'm lazy, overst33r has forced me to pull up the old post on the S2000 fuel efficiency vs. speed debate.

In order to keep this thread from getting further off topic, please see:

faster=better mpg

 

I can agree that the motor is not as efficient at lets say 2000-3000RPM as it is at higher RPM's due to its design, but if going 80mph at 4200RPM gets them 30mpg, then an S2000 with 4.77 gears should get even better mileage because it is going even slower at the same RPM, meaning it has significantly less air resistance, and therefore better gas mileage. Funny thing is I have yet to see a thread saying that gears offer better fuel consumption. I'm not saying it is impossible, just highly unlikely for any car to get better gas mileage at 80mph than at 55mph. Considering the variables of how people calculate their mileage, windspeed, climate, throttle position, etc., this discussion doesn't really have a solid answer until an experiment is conducted in a controlled manner.

Now most people will have an excuse to speed because the S2000 gets better gas mileage at higher speeds

 

That's what I'll tell the cops