97 850R poor gas mileage or lead foot?

[koffinb]

Hey I just wanted to hear from some of the other R owners in here regarding gas mileage. I average anywhere from 16-18 purely city driving with some spirited behavior and on the highway I get around 25. Is that correct? Am I driving too hard or is there something wrong? 120k set once was performed on time and I am now at 140k. No misfires or codes, engine pills as it should. I try my best to keep it in Econ mode but it's just so tempting. 93 octane is always used as well.
I guess coming from a base manual s70 I was expecting to see 28/29 on my long 5 hour highway cruises. I was a bit surprised to see I was only getting 25. And yes I do the math by hand I do not go by the trip computer. With the larger tank I was hoping to see 350-400 miles per tank.
Anyone else want to chime in on this?

[alschnertz]

Your numbers don't surprise me. Especially with ethanol blended fuel.
In our '95 854T, my daughter would get around 19 mpg in town.
I've taken over the car the past 6 months and average about 24 mpg in my suburban driving.

[rspi]

In my '95 R I get around 21 around town, average speed of 20 mph. On the highway I get between 26 and 29 depending on how much crap I have in the car and which way the wind is blowing. Speed limits around this side of the globe is 75 mph.

I only use S, have a K&N air box filter, use 91+ octane, have had low boost issues and use full synthetic oil. The most common issue that I have found with people getting lower fuel economy than me is when people drive with a bad thermostat that doesn't warm the car up fast enough and keep it up to temp well. The needle in the car will stay at 3 o'clock when it get to 175 and stay there till the temp reaches 240. If you ever see it tweek down, the thermostat is likely bad and running the car rich.

[RussB]

My annual average mpg is around 24, all driving combined with 10% ethanol crap they have here in the northeast. It has been the same for 12+ years.

If I wanted around 40mpg I'd buy a Prius

[matthew1]

Koffin: lead foot. Normal numbers.

[tryingbe]

5 hour highway cruises. I was a bit surprised to see I was only getting 25.

At what speed?

[koffinb]

In my '95 R I get around 21 around town, average speed of 20 mph. On the highway I get between 26 and 29 depending on how much crap I have in the car and which way the wind is blowing. Speed limits around this side of the globe is 75 mph.

I only use S, have a K&N air box filter, use 91+ octane, have had low boost issues and use full synthetic oil. The most common issue that I have found with people getting lower fuel economy than me is when people drive with a bad thermostat that doesn't warm the car up fast enough and keep it up to temp well. The needle in the car will stay at 3 o'clock when it get to 175 and stay there till the temp reaches 240. If you ever see it tweek down, the thermostat is likely bad and running the car rich.

Wow. Those are really good numbers. My thermostat is not stuck open, as a matter of fact it was replaced a year ago and the needle stays in the 3 o clock position all the time. I am beginning to think it's just my driving habits? I don't do any crazy acceleration from lights or anything like that but I find myself always in boost. Kind of hard to drive these things without getting into the boost.

[koffinb]

My annual average mpg is around 24, all driving combined with 10% ethanol crap they have here in the northeast. It has been the same for 12+ years.

If I wanted around 40mpg I'd buy a Prius

Do you drive in Econ mode or sport mode? And I take it you do mainly highway driving? The stuff here in virginia contains 10% ethanol as well. That plays a role?

[koffinb]

5 hour highway cruises. I was a bit surprised to see I was only getting 25.

At what speed?

Average of 70mph

[koffinb]

Koffin: lead foot. Normal numbers.

How do I train myself to not have a lead foot in a car like this??