What is the optimal speed for max mpg?

[lexsum]

can anyone (esp our hypermilers on here) assist with this question. also is the optimal speed different for each mode?

thanks

[DaveyG]

Originally Posted by lexsum

can anyone (esp our hypermilers on here) assist with this question. also is the optimal speed different for each mode?

thanks

I think its 55 to 60.

[91CRXTC]

my old man is constantly on the road for work, he started to not go past 55mph and has saved a **** load of gas. So i would say dont go faster then 55-60mph.

[BlackBullet]

I was actually playing around with that and what I found to be really good was 41 in 6th on Eco.

[bizzybear]

found this on cleanmpg.com and this was for the 6MT

The Eco Mode based steady state - Cc FE numbers are as follows:

•45 mph - 58 mpg
•50 mph - 53 mpg
•55 mph - 49 mpg
•60 mph - 46 mpg
•65 mph - 43 mpg
•70 mph - 38 mpg

[swat49833]

I think bizzybear numbers are correct, at least from my experience. I have an 11 CR-Z CVT It seems to love 45-55, the tenths tick upward alot slower as you gain in speed even if you hold it steady...

[LeeMoon]

Just for kicks, I drove over to one of our islands today. I reset Trip B once I hit the causeway (55 mph) going onto the island. After driving around the island for a while (and stopping to take a few photos) where the speed limit was 35 mph, I headed back home (mix of 45, 50 and 55 mph) and got a 54.4 mpg average for that trip. This was using Econ at 35-55 mph speeds in very light traffic and the a/c set to auto at 74 degrees. Oh yeah, my car is the EX with CVT and Navi.

Here's the photo I took after getting home...

[JnC]

Simply put for a manual, the best speed for mpgs should be the slowest that you can drive (lowest rpm) in the highest gear. This should be the same for each mode as you only have one set of gears.

The CVT may have different responses as it does adjust the engine speed based upon mode.

However, lugging the engine is not good for the long term. And the lack of response and irritation to other motorists aren't good either.

[oldchap14]

JnC is right on...the slowest speed will provide the best mpg because of lower wind resistance. But it might be most efficient at 18 mph in 5th gear, rather than 24 mpg in 6th gear (just an example, not necessarily true). And if the road is quite flat, you probably won't be lugging the engine at steady rpm even at these low speeds.

If competing in a time/speed/distance rally in a modern car, it's best to accelerate to the desired speed as quickly as possible, rather than slowly accelerating to the "average" speed. This is because fuel injection is more linear than carburetion with secondary jets that open under hard acceleration. To hit your average speed, if you accelerate slowly, you will have to spend more time at speed higher than the desired average, and that means more wind resistance resulting in lower mpg.

[JnC]

Originally Posted by oldchap14

If competing in a time/speed/distance rally in a modern car, it's best to accelerate to the desired speed as quickly as possible, rather than slowly accelerating to the "average" speed. This is because fuel injection is more linear than carburetion with secondary jets that open under hard acceleration. To hit your average speed, if you accelerate slowly, you will have to spend more time at speed higher than the desired average, and that means more wind resistance resulting in lower mpg.

Which is why for the life of me I wish the ECON mode did not remap the throttle position. I'd rather accelerate quickly to speed then drive with a light touch. I suppose that's what the buttons are for, but still...