Injecting More Power Into A Diesel: Water/Methanol Injection Kit

Many wonder how water alone can increase power since it isn’t a fuel. Water increases power through two main mechanisms. First, it lowers charge air temps, which increases air charge density (more oxygen available for combustion). When water changes state from a liquid to a gas, it absorbs heat. How much heat depends on the total surface area of the droplets, which is why atomization is so important. With constant volume, the more finely atomized the droplets, the more total surface area. Secondly, expansion takes place as the droplets change state during combustion creating the “steam effect” which pushes down on the piston creating additional torque. Also, this is “safe power” in that this torque is predominantly created as the piston is going down during the power stroke after TDC.

OR: Does water-meth injection into a diesel engine cut emissions? Wasn’t this used as far back as the early 20th century?

Snow: Water/methanol injection has big advantages with emissions. Specifically, NOx is reduced up to 70 percent and particulate matter (PM) is reduced up to 50 percent. This is significant because these are the two emissions that the EPA is most concerned about.

In the late 1800s to early 1900s, Rudolf Diesel recognized the benefits of water injection in diesel combustion as a way to get more useable work out of the heat of combustion. Just as turbocharging is a way to scavenge normally wasted energy, water injection is used for the “steam effect” in combustion where additional torque is produced as the water droplets go from liquid to vapor.

OR: Is it legal? If not, why not?

Snow: The key to California Air Resource Board (CARB) certification and getting an executive order number for a product is proving that it doesn’t make emissions worse. Since water and water/methanol injection in a diesel reduces emissions significantly, it is just a matter of proving it with a CARB-approved testing protocol at a CARB-approved lab. This unfortunately takes a fair amount of time and money. We are in the process of getting the necessary certifications to satisfy CARB (and thusly the EPA) with a water/methanol injection kit. In certain states, emissions testing is not yet done on diesels, so diesel owners in those areas do not need to worry about emissions exemptions.

After doing some towing with our MPG-MAX system engaged, we can definitely tell the power difference and we can see a definite EGT drop coming up steeper grades. We’ll need to do some more testing before we can give you accurate fuel economy changes with the Snow Performance kit (and maybe even find a dyno to see the rear-wheel power differences), so look for a future report in our Long-Term Updates column.

After doing some towing with our MPG-MAX system engaged, we can definitely tell the power difference and we can see a definite EGT drop coming up steeper grades. We’ll need to do some more testing before we can give you accurate fuel economy changes with the Snow Performance kit (and maybe even find a dyno to see the rear-wheel power differences), so look for a future report in our Long-Term Updates column.