Filling up with the good stuff

[JayG]

Originally Posted by Perfectlap

^ I never run with more than half a tank. I've convinced myself that less weight over the life of the car is easier on the consumables. And now you tell me I'm losing a dollar!!!

Originally Posted by Giller

Putting a couple gallons into the car over and over is silly - but there is something to be said about keeping the tank on the lower end (well, not full anyways). Gas can add a lot of weight to the car. I know people who swear by only keeping the tank half full and they see a 'big' improvement in their MPGs. They also feel the car performs better (it's lighter). Plus they say it keeps the gas fresher, especially in a car that sits for extended periods.

Not sure how accurate it is, but the belief is out there.

WTF ????

half a tank to save weight for better MPG? You must be joking!!!
Gas weight just over 6lbs per gallon so 8 gallons is approx 48 lbs

I know for racing, they watch every pound, buy that is to squeeze out every ounce of performance and sometimes has to do with rules as well.

As far as effecting MPG, sure, it will have some effect, but probably measures in 10ths at best. If you are so worried about weight, did you take out your spare and toolkit? Running lightweight wheels? No extra crap in the car?

Big improvement in MPG, no way!!
Big improvement in performance? get driving instruction, its unlikely you drive anywhere near the top of the performance envelope in your Boxster. 50 lbs ain't gonna make a difference