[Slicktop]

Just reporting an unusual trip and MPG results:

Total trip mileage: 255 miles RT - all highway/non-commute 75-80mph. Destination at 2000FASL and most driving is at or near sea level. Temp 65-78F
Clear, dry road/weather conditions. AC off. TP to spec; fuel: Union 76 HiPerf. 91 Oct

Outbound MPG: 27.67mpg Inbound: 33.69mpg

I've done a similar trip and could only wring out 24mpg. The only change was switching from Mobil 1 15w-50 to Mobil 1 0w-40(EuroBlend). I seriously doubt the oil weight change had such a dramatic impact on MPG.

 

[430]

There are many factors that can effect gas mileage. I know one time when I was in college and returning home for summer, my normal route 75-85mph I got 45+ mpg. This on a car that with hwy crusing normally got in the mid 30's at best. There had been no changes to the car before the trip. How did I get such great gas mileage? I have no idea.

 

[DEATHERAGE]

wind resistance, tire preassure, gas octane levels, drafting people on the freeway.....

lots of stuff

 

[flysmith]

Wind!