Water-methanol injection is nothing new. While it has recently become a hot item in the racing and towing communities, its roots lie in pre-WWII fighter planes. The U.S. military began injecting a mix of water and methanol into the P47 Thunderbolt’s engine, boosting horsepower numbers in some cases close to 2,000 hp over stock. This allowed for much shorter take-off’s and increased power for dog fights while enjoying better fuel economy at the same time.

Using a 2D digital computer controller with multiple engine monitors, Snow Performance has taken this historically tested technology and adapted it to today’s modern engines for safe and reliable power. For us RVers, with our large and heavy homes-on-wheels, the Snow Performance kit makes rolling on ramps, climbing hills, and passing semis eons easier. Snow Performance claims (and we confirmed) that there are gains of 1 to 3 mpg and about 20-percent horsepower, as well as an average 300-degree drop in exhaust gas temperature (EGT).

The Science

When injecting water-methanol into an internal-combustion engine, the mix creates what is known as a chemical intercooler. Depending on the power plant, nozzles are installed in the intake and generally spray a 50/50 mix of water to methanol. The mist then enters the combustion chamber and instantly cools the incoming air. This creates a much denser air charge allowing for a more complete burn equaling more power. As a byproduct of this more complete burn emissions are drastically reduced as well. Snow’s digital controller progressively injects this mix giving you smooth, safe, and green power.


After installing the MPG Max Kit, we picked up our Carson Trailer, topped off the Snow Performance tank with a 50/50 mix of water to methanol and filled up on diesel. Our testing plan was to start and stop at the same gas station, at the same time of day with the intent of having the same ambient air temperature for each run. The route took us up and down 36 miles of six-percent grades and ended with a 24-mile run through city streets. We ran this loop four times to really give the MPG Max Kit a true test. After making two “control” laps with the injection turned off we were ready to start spraying the water methanol.

The first time the pump kicked on really was an odd feeling. Starting at the base of the hill we accelerated until the boost reached 8 psi. At that point the Snow Performance controller turned on the first stage of injection. With the accelerator pedal in the same position the truck climbed and climbed. It really does feel as if someone else is rolling on the throttle for you. EGTs were drastically less and we were able to maintain a higher, safer speed.

Testing Results: Hill Climbing

MPG Max Turned Off
EGT: 1,100-degree average
Sustained Speed: 45 mph
Mpg: 10.11

MPG Max Turned On
EGT: 900-degree average
Sustained Speed: 60 mph
Mpg: 16.35

(Note: These results were found while testing on an exceptionally mountainous highway. This is where the Snow Performance kit really excels. When testing on flat ground the mpg gains were evident but much less substantial. On flat ground we saw an average gain of 1.23 mpg over stock.)

Snow Performance
1017-A East Highway 24
Woodland Park
CO  80863
841 S. 71st Avenue
AZ  85043