Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - BMW M3: "The optimal speed for fuel economy in this car seems to be around 80mph"

Yahma · 09-08-2008, 01:55 PM

I believe it!

According to the Top Gear segment, it would seem that the BMW is more efficient than the Prius at Autobahn speeds (100 mph), where the little prius engine is seriously struggling just to maintain that speed.

I drive a BMW 325i (2006 model), and have been keeping close tabs on my fuel economy while commuting. I have a long highway commute everyday (Hollywood to San Diego) of about 125 miles. Over the course of many tanks, my trip computer says I have averaged ~38.4 mpg @ 76.8 miles per hour. The MPG figure is verified by calculations done at the pump.

This morning I got 40.6 mpg for my 125 mile commute, but my average speed was 69.5 miles per hour.

The best gas mileage for my 325i is between 68-75 mph. Going slower does not improve economy, while going faster reduces economy. BMW's were designed for the Autobahn, and based upon my informal testing, it seems the numbers posted for the M3 are legit, considering the M3 has significantly more power than a 325.

09-08-2008, 01:55 PM	#25 (permalink)
Yahma EcoModding Lurker Join Date: Sep 2008 Location: USA Posts: 2 Thanks: 0 Thanked 0 Times in 0 Posts	I believe it! According to the Top Gear segment, it would seem that the BMW is more efficient than the Prius at Autobahn speeds (100 mph), where the little prius engine is seriously struggling just to maintain that speed. I drive a BMW 325i (2006 model), and have been keeping close tabs on my fuel economy while commuting. I have a long highway commute everyday (Hollywood to San Diego) of about 125 miles. Over the course of many tanks, my trip computer says I have averaged ~38.4 mpg @ 76.8 miles per hour. The MPG figure is verified by calculations done at the pump. This morning I got 40.6 mpg for my 125 mile commute, but my average speed was 69.5 miles per hour. The best gas mileage for my 325i is between 68-75 mph. Going slower does not improve economy, while going faster reduces economy. BMW's were designed for the Autobahn, and based upon my informal testing, it seems the numbers posted for the M3 are legit, considering the M3 has significantly more power than a 325.