I get on avg per tank (south Florida - no hills):
16 mpg in the CS
13.5 mpg in the CTTS
I didn't buy them with a thought of MPG. I have not owned a vehicle in 30 years that got to the 20 mpg mark. Porsches (and me) are all about performance & the 2 don't go hand in hand most of the time.

 

Mine is 100% stock, 05 CTT.

 

Mine is very modded, id say one of the most modded 955 without changing turbos

 

I agree I just think it's nice to have a 600hp suv that can get 20mpg.

 

On my last trip fro SF to LA I averaged close to 20mpg, otherwise it's around 15mpg with a 50/50 city/hwy split. The hills around the SF Bay Area really takes it's toll on mileage numbers.

 

I was getting around 15MPG but after I put a fresh set of plugs and coil packs in I bumped it up to 19MPG. 957T with 43K on it.

I plan on installing bypass pipes this weekend, hoping it will give it another MPG or so. Although I didn't by the Turbo for its MPG capabilities

 

I'm quite impressed by the numbers you guys are seeing. The best I've seen so far is 16.75 mpg and that was up and down a few mountains!

I'm averaging 14.7 mpg over the life of my ownership. It must be the in town traffic that's bringing it down.

Not that I particularly care seeing as I'm in the same boat at mrbrianc; I've never had a vehicle achieve over 20 mpg.

 

In straight city driving I see about 12.

 

My CTT gets 10 mpg in stoplight to stoplight city driving. 12 mpg in mixed city driving. And 15 - 17 in straight freeway driving. But I tend to get lower than average mileage in most cars I drive (and shorter tire life too). I think my shoes may be heavy.