Crownvic

Hi,

You can imagine that I am not figuring into a 400hp car purchase trivial stuff such as fuel savings or ecological considerations. For TT thrills some would even drive with a seagull strapped to their exhaust pipe.

But what has me puzzled is the spontaneous claim by a used Porsche specialist that the 993TT gets 22mpg on the highway cruising at 70mph. Not far from the 25mpg he says that a non TT engined car gets at the same speed.

Who is this guy kidding?

/Vic

R993TBO

I get 26mpg on a long cruise doing a steadyish 70mph.

Bill P.

Hmmm, according to the on-board computer, I usually average around 13 in mixed driving. However, I wouldn't be surprised if the milage in 6th gear at a constant 70 would be 22 or more. Just an observation from a few long road trips when stuck in that "no fun zone."

Bill

Rassel

Hohohoho,

Lets flip this around! On the track......

I've gotten as low as below 6mpg

On highways, I guess it possible to maintain above 25 if you've got the wind in your back, sun is shining and you just got your pay check...

But normal driving I don't get above 20.
(Hey, I can't help it, it's wicked fun to hit the gas from time to time!)

Crownvic

Thanks guys, I am just trying to gauge the depth of the bull sale people are feeding me. I guess they aren't as dishonest as I imagine. Spoke to a few story teller lately and it just poisons you. Thank goodness for Rennlist.

This means that the 993TT give the most bang for the buck. Every penny of extra fuel spent translates into performance, and is not wasted in mechanical inefficiencies like in so many other cars that hog gas while at idle. Bravo Porsche!

/Vic

Bill (NC)

I also get 26 mpg at cruise at 70 mph, so your dealer, if anything, is conservative. Course I also get 5 mpg on the track, hehe.

dbf73

Vic - when I drove my car home from Florida, I averaged 24-25mpg on the freeways. Around town, I'm lucky if I hit 15.

JJayB

In combined driving; car on trailer to the track and on the track, I get 25mpg

speedlimit2

recently did 297 mile trip (mainly motorway) middle of the night average speed 78 mph 21.8 mpg according to the OBC

911/Q45

I got 22 mpg stock and, after my 3.8 Andial upgrade, get 24mpg @ 80 mph on crummy CA gas.

jmayzurk

I get 24-25 MPG on the highway if I behave myself, and around 13 MPG around town.

-Jeff

fc-racer

Off boost, you essentially have a low compression normally aspirated engine that consumes minimal fuel. The motronic with O2 also operates in closed loop during part throttle cruising giving ideal fuel conditions. Add all of this up and you get hot-hatch fuel economy with super car performance available at the tap of the accelerator.

ca993twin

Gas mileage while cruising is a good measure of aero resistance, rolling resistance and engine efficiency... all interesting factors. My TT typically can get about 24 mpg at a steady 70mph, but "real world" cruising it gets more like 21.

fc-racer mentions an interesting, but often overlooked point about our engines... they are low compression, and hence much LESS efficient in no-boost applications than their high-compression equivelent. This pretty neatly explains our lower fuel mileage than our NA brethern on steady-state cruise speed, since most of the other factors are the same, especially with the C2S and C4S cars.

Variable compression, that's the ticket. Wasn't somebody working on that idea? Saab? Volvo?

Rassel

SAAB, indeed had a variable compression engine called SVC.
1.6L, 30% more fuel efficient than a normal engine and 200+ hp. What I heard, they pulled the plug on the project. Perhaps Thomas knows more specifically what happened to it.

CP

Since mine is a C2, NB with aero-kits abound, I once got 28 MPG at 65 MPH constant speed between Sacramento and Los Altos (148 miles). That was in 6th doing 2,400 RPM all the way.

So it can be done. Although I practically gone insane restraining my right foot for 2.5 hours.

CP