Boxster Gas Mileage Experiences

hytem · 07-09-2007, 06:41 PM

I just got back from a trip to the mountains of eastern PA with my recently acquired 03 Boxster, and averaged 35 mpg in mostly highway driving (some backroads driving with top down/side windows up). I checked the mileage on several fillups. Highway speed range 55-75. Moderate to conservative driving.

The EPA highway rating is 29 mpg for this car. I wonder if the higher mileage is due to the 18" wheels (more distance per rev.)and the stiffer all-season tires (less rolling resistance). I'm seeing about 26-27 mpg in short trip suburban driving. 5 speed transmission.

I suspect the EPA numbers are conservative--to say the least.

What is the mileage experience out there with these cars? I'm pleasantly surprised.

JMatta · 07-10-2007, 03:43 PM

Those are impressive numbers. I estimate I get around 25 mpg highway in my '02 S, which is far better than my Jeep Grand Cherokee. Of course, my local driving mpg is much lower, as I like to get her in the upper revs frequently.

hytem · 07-10-2007, 07:50 PM

I posted this in other newsgroups, and the figures I saw for others were all over the map--depending, it appears, on the type of driving they do. A few have seen 32 mpg in highway driving, which is close enough to 35 I've seen.

I believe the on-board computer helps a lot in maximizing gas mileage, since you can continuously monitor gas mileage as you are driving. I also think the low drag coefficient (.29?) must help a lot on the highway, along with that spoiler.

Grant Lenahan · 07-11-2007, 09:45 AM

driven moderately aggressively with a 2.7 5-sp.

18" wheels, if properly fitted do not increase circumference.

Grant

hytem · 07-21-2007, 02:04 PM

I monitor the mileage with the on board computer after each fillup (1/4 to 1/2 tank). In several short trips around town, including a long backup due to tree trimming, I was getting about 22 mpg. One round trip on the highway of almost the same total distance, the mpg went up to 26. That figures to over 30 mpg on the highway. The cold starts and traffic delays are the gas eaters.

Another killer are traffic lights, which keep increasing. They are putting them in now at T-intersections, where they aren't usually needed. The local pols have no concept of saving gas--yet.

In France, there are few traffic lights--they use roundabaouts or rotaries, instead. I realized that after driving around Normandy for awhile. They save on gas by keeping the traffic flowing. Very un-American. But gas is more expensive over there.

JMatta · 07-25-2007, 04:04 PM

Just returned from a 250 mile trip in my 911 to attend the vintage race at Road America. How does 12 MPG sound? Should have put the car on a trailer for that $...

jvaski · 07-27-2007, 09:49 PM

I have a 01' STD Boxster. I seem to be getting around 28mpg regardless of how I drive it and where I drive it. Most of my trips are from Tahoe to the Ca north coast . It still averages around 28mpg even pulling the mountains on the way back.