Mazda3 2.0 Manual can't break 40mpg

[ever_green]

my drive is about 25min long, even on long road trips mileage never gets better than 40-41mpg. Yes I also think my shifting improvements won't change the game. Even when I'm not in an economy mindset and am rushing to work I only do marginally worst when letting revs climb all the way to say 3500. For example recently when i changed my shifting behavior from my first post to other suggestion my mileage only improved 0.1 L/100km vs usual which probably falls into margin of error anyway. Yes slowing down helps a lot but since the road is 2 lanes only with lots of volume traveling in excess of 75mph it is not always possible. What I'm complaining about is the fact that this car is epa rated at 37mpg highway and 27 combined and I can only do 3.5 mpg better than that. In my previous cars I have seen 6-8 mpg improvements over EPA easily. My gas guzzling 3650lbs awd Mitsubishi gets about 28 mpg on the highway cruising @3k RPM @65mph with only modification being narrower low resistance winter tires yet it's rated at 22mpg highway :\ It even improves further to 30mpg if i coast more or reduce to 55mph some parts of the way. This makes me wonder if an engine that generates 300hp gives max 30mpg is inefficient compared to one that makes 155hp with max 40mpg, and whether it's worth sacrificing 150hp and 4WD for 10mpg improvement?

[MeteorGray]

I live in Louisiana and am averaging about 44 mpg with my '15 Mazda 3 automatic in a driving regimen consisting of about 90% highway and 95% air conditioning use.

I don't hypermile per se, but I do try to drive a bit slower than the average traffic around me when I can do it safely. The speed limits on the highways I normally drive on range from 55 to 75 mph. When I can, I drive 55 in the 55 mph speed zones and around 60 in the higher speed zones when I can do so without getting hit, but when so threatened I step it up closer to the speeding zombies around me.

For me, it's all about the average speed and, of course, such things as wind velocity and direction.

Since I have an automatic, I can't comment on shifting strategies and RPM.

[ever_green]

Originally Posted by MeteorGray

I live in Louisiana and am averaging about 44 mpg with my '15 Mazda 3 automatic in a driving regimen consisting of about 90% highway and 95% air conditioning use.

I don't hypermile per se, but I do try to drive a bit slower than the average traffic around me when I can do it safely. The speed limits on the highways I normally drive on range from 55 to 75 mph. When I can, I drive 55 in the 55 mph speed zones and around 60 in the higher speed zones when I can do so without getting hit, but when so threatened I step it up closer to the speeding zombies around me.

For me, it's all about the average speed and, of course, such things as wind velocity and direction.

Since I have an automatic, I can't comment on shifting strategies and RPM.

yes of course speed counts. but several differences here. i get 40 mpg but i mainly cruise at 65mph, tires are sticky winter rubber, temperatures are at or below freezing temperatures and i am running winter gas. so i think that accounts for your extra 4 mpg. in the end it’s still not impressive to me for a 2017 year car. not very different from my first car which was a 2000 corolla.

[Ecky]

Your new car is 600lbs heavier, has about 10% more interior volume (probably correspondingly more frontal area/drag), and 25% more horsepower. The Corolla was already pretty near top of the food chain in 2000 and the 1NZ is a great engine - basically the same engine is still sold in several Toyota models.

Anyway, looking at the BSFC chart you posted, it appears the SkyActiv engines don't so much have a better peak BSFC (though it's very good), but rather a much larger area of high efficiency. With many cars, dropping out of the ideal rev range has a much larger impact on economy.

[Dean in Milwaukee]

Surprising the 3 isn't doing better. My 2015 6 usually gets 39-41 on hwy trips just by setting and forgetting the cruise, and has done a best of 45.7 when the driving conditions were unusually optimal. http://ecomodder.com/forum/showthrea...tml#post519464

[Joggernot]

Can the BSFC map be copied to the following thread?

Brake Specific Fuel Consumption (BSFC) Maps - EcoModder

[Daox]

Good idea Joggernot. Its done.