911sport

I just returned from a trip in the mountains of Eastern PA, and averaged 35 mpg on my recently acquired 03 Boxster. Mostly highway driving, some with top down/side windows up. Little or no AC. 92 and 93 octane gas. I checked this with fillups several times.

Since the car is EPA rated at 29 mpg highway, it would appear the EPA ratings are conservative. I do have 18" wheels and all-season tires just installed. I don't know if the greater distance per revolution with 18" wheels or the stiffer all-season matrix (less rolling resistance) are factors. I'm seeing about 26-27 mpg in short trip, suburban driving.

Any similar experiences with these cars? A pleasant surprise.

Tierce

in the mountains??? 35MPG??? yeah right.

I get 22-23 with some highway, but 35? it must have been mostly downhill. i guess they've improved a lot in 3 years.

that's incredible.

Tierce

360 posts, i'm back where I started. yippee!

Macster

a skosh a very small skosk over 30mpg. Oh, car has 17" wheels/tires inflated (cold) to recommended pressures (29psi front, 36psi rear).

'course, this best mileage the result of strictly freeway driving, but at legal (ahem) speeds.

Were I to restrict myself to 70mph or 65mph using cruise control, the car might deliver 35mpg, outside of the mountains and higher elevations of I-40 that I frequently cover on my extended road trips back east.

My city/freeway commute driving with typically some stop/go even on the freeway sees gas mileage hovering around the 25mpg to 27mpg. A spark plug change -- the old ones are way past due for replacement -- could see a mpg or two improvement.

Sincerely,
Macster.

911sport

I forgot to mention--didn't use the cruise control. Uphill to the mountains, I got 35.2 mpg. Downhill on the return home, I got 36.5 mpg. Had the AC on a bit on the return and top speed 76 mph. Mostly 60-65 mph. Transmission is 5 speed.
Tire pressures 29/36 cold.
The 03s are EPA rated 20/29 mpg.

blueillusion97

I get 26-27 average street and freeway driving with AC on. I dont know about how it is in other places but try driving 60mph here and you will get runed over by 80 year old grandma in a semi truck.

Bull

18s shouldn't have any different circumference than 17s given the different aspect ratios.

911sport

LOL. You got that right. Lots of cowboys and cowgirls out there in their gas guzzler trucks.

unklekraker

dude..i get an average of 20mpg, combination of highway and city driving
99' Tip w/ 18" and desnorkled and 55k mi.

I always use the sport shift mode and change gear @ 4k rpm and lots of accelaration. I guess i need to change my driving habit...
On AX..i get worse mpg....

First986NJ

You sure you don't live in Jersey too ?


BTW....I get 23-25 around town, 26/27 if I keep my foot out of it (which I don't). On a trip to Mass last year I got 32 avg. and I was flying up 84 and Mass Tpk.(A K40 makes you brave...more than a few 90+mph stretches) Probably could have gotten 35/36 at the speed limit.

Mine os MY03 2.7L @ 20k currently; Headers/FabSpeed exhaust/EVO intake/ROW M030/ 18" lightweight Carerra wheels/ Pirelli's @ 30 psi.

P.S.....any NJ/NY/CT/MA policemen that might be looking in on this board: It's all a bunch of BS - I never really drove that fast through your fine states.

BobbyB

35 mpg??? You're one lucky dude -I'd start checking my odometer, computer etc. On the serious side, I get about 18-20 combination city/hwy. Strickly Hwy avg about 75+, I'm around 26 - 27. I have an S, 18' wheels and lowered. I've never seen 35 but I think once for a minute or two I hit 28. If you continue with 35, count your lucky stars. Cheers

911sport

The new Boxsters are rated at 23/32 mpg. I wonder if those 03 EPA numbers are accurate.
Could be earlier years' numbers. They seemed to be refining fuel efficiency yearly. Gas is expensive in Europe compared to here. The mileage indicator, by the way, read accurately on the trip I took, which I've measured with other cars.

Doug&Julie

All of my Boxsters ran the same range...low-mid 20s in the city, high 20s on the highway, with an occasional tip just over 30mpg on a long trip. But the best I ever measured was 31.5 on my first Boxster some 7 years ago. I tend to drive average-mildly assertive, but always trying to at least be smooth. Highways I usually run 5-10 mph over the limit.

JohnVitamvas

I get around 22MPG in the city, with a decent amount of hard acceleration.

I've seen 28MPG on the freeway, but that's with extended periods of 80+. I suppose if I went 65-70 (and got run off the road) I would get over 30.

JV

fast1

I have an '07 987 and I'm averaging 23 MPG in mixed driving. I only have a little over 700 miles on the odometer, so I expect gas mileage to improve after break-in.