Question very high MPG cars in the Garage (60-80 mpg Honda Civic?)

[Jim-Bob]

If you really wanted to pick nits, you could even challenge the use of EPA combined cycle as the yard stick and instead use your own percentage of city/highway driving at the EPA rated mileages for those kinds of driving to devise a personal combined cycle baseline. For me, that would change things drastically as I drive 100% city on a daily basis and rarely ever go on the interstate ( the car delivers pizza at a store 1.8 miles from my house and I rarely go more than 5 miles from home). Thus, my base mileage would be based off of the 37 mpg city and NOT the 40 combined that it is now. Could I fudge the numbers? Yes, but that would be cheating and I am not willing to win (for lack of a better term) by illegitimate means. It proves nothing in the end and just gives me shallow bragging rights that I cannot back up. It adds nothing to the discussion here and helps no one improve their fuel mileage.

[JasonG]

So Jim-Bob, I gues its miles per pizza

[Piwoslaw]

Or pizzas per gallon

[JasonG]

Just noticed the miles per pizza, funny !

[dieseleverything]

Originally Posted by Piwoslaw

If someone is running on gas with 15% alcohol, then should his fe be 15% better?

Why not, if they are getting the alcohol for free?

[dieseleverything]

Originally Posted by dennyt

Agreed. It's admirable that you're using WVO, but you're still burning the same amount of energy, and producing the same amount of emissions. Claiming a MPG assuming WVO is exempt tells us nothing of the efficiency of your car, your route, or your driving techniques.

Originally Posted by ShadeTreeMech

Let's not forget that, despite WVO being a cleaner fuel (not CLEAN, just better than diesel), it still puts out carbon emmisions.

Actually WVO produces less emissions, and because it comes from a plant, so in the whole cycle of things the WVO process as a whole produces less emissions than running on petro diesel. Plus it's technically recycling something that was used for something else.

See http://www.buffalobiodiesel.org/svo_emissions.pdf page 8

[dieseleverything]

Originally Posted by Old Mechanic

Maybe you should talk about miles per penny.

Fine. $4/120mpg=.03 So 3 cpm or .33 miles per penny. What's yours, if you want to go that route? You would have to use a lot of free gasoline from totalled cars to get .33 miles per penny.

Reasons for becoming a member range from the economical to the ecological.

I'm here to save money, not reduce the amount of fuel that flows through my injection pump.

[PaleMelanesian]

Oh, wow. How did I miss this?

It's all about technique. I'll work up a longer explanation in a bit.

[PaleMelanesian]

Engine efficiency is at its highest at low RPMs and fairly high throttle. If you want maximum efficiency, keep the engine operating there, and shut off the engine when you don't need power. "EOC and P&G".

This is key.

I have no lean burn. I'd likely use some if I had it, but not always. Bold part is absolutely true.

My routes are also low-speed. Only one portion has 55 mph limit, the rest is 35/45. My rolling average (not counting stops) is 30-35 mph.

The only thing keeping me from duplicating these numbers away from home is higher speeds on the highway. There, I get 60's instead of 80's mpg. In other cities I can do nearly as well as at home. If I drove such speeds regularly, I'd be modding my car more for aerodynamics.

It has taken me years to get to this level. It's in the log.

Pulse and EOC glide is my primary mode of driving. If the engine isn't providing acceleration, it's off.

I'm not alternator-less as long as the engine is running. EOC is naturally alternatorless. Since I do that so much, my battery runs low and I use a trickle charger at night to top it off. ~20c of electric per tank, not much at all.

I do lots of clutching - maybe 50 P&G cycles per 10-mile commute. That's one clutch to go neutral, then two to do a smooth bump-start, then sometimes a gear shift during the pulse. My clutch is handling it fine at 184,000 miles. Yes, it is tiring, but I have done it for a 600-mile highway trip.

About 3/4 throttle and 1500-2200 rpm is best for accelerating. Higher throttle goes into fuel enrichment and wastes fuel.

Rolling hills like I have are great for P&G. I pulse on the uphill, glide down the other side, maintainging fairly constant speed. That makes me more predictable for surrounding traffic. I time my P&G cycles to accomodate traffic with minimal disruption.

[PaleMelanesian]

Oh, and I run a quarterly fuel economy contest at another site. Competing for the best mileage each and every day forces you to improve.

A Scangauge is critical to my success.