Re: Acetone will increase MPG?!?!
Well, I did a shorter version of the desert test yesterday in my '01 Limited. Ended up going from Pasadena to Calico and back again, a
round-trip of about 240 miles.
Most of the drive was at sustained freeway speeds with the cruise control set to 75mph, corrected against the GPS. Not 100% accurate, I know, but my speedo overreads by a consistent 3-4mph so it didn't hurt to have at least some form of second opinion. Departing temperature was 80degF; arrival temperature was 60degF.
On both the outward and return journeys, there were massive wind gusts (bad enough that semis were pulling over to wait for them to die down) for approximately 10 miles at the same location. This knocked cruising speed down to about 55mph as the XJ struggled against them and also shot fuel economy right into the toilet.
Pasadena's elevation is given as
864 feet above sea level; Calico's at
2600 feet. Note that this doesn't equate to an 1800-foot straight climb: the Cajon Pass tops out at 4160 feet and you have to cross this in order to get out to the desert communities. Outbound is mostly uphill, inbound is mostly downhill.
With acetone in the tank at a concentration of one ounce to every five gallons (4oz. total) and a fresh fill with 87-octane from the same Chevron I always go to, round-trip average economy was 19.6mpg. Both the trip meter and overhead console were zeroed out before leaving. Usually I'd get around a 16mpg average on this run - I've done it several times before, so am fairly familiar with what to expect. This translates out to a roughly 20% improvement, which possibly could've improved further with less wind and no seven-mile side trip into the canyons in 4FT
So while it's not exactly empirical evidence, it is giving some credence to the theory that acetone does help. Using the cruise control probably didn't hurt either, since it's more or less eliminating trailing throttle.
In any event, at 85c per application, it's well worth it at today's gas prices.
