Duramax Diesel Engine Horsepower & Torque Uprgrades- Dura Maximus

Upgrades, Part 3
Snow Performance is a trusted name in the diesel performance aftermarket because the company's owner, Matt Snow, insists on building a high-quality product that provides consumers with an excellent horsepower gain per dollar spent. We like Snow Performance water methanol kits because they allow end users added safety in regards to exhaust-gas temperatures. The MPG-Max system is the latest kit from Snow Performance. This particular system is designed to inject a mixture of water and methanol at a preset turbo pressure or EGT set point. It also allows for a smaller amount of water and methanol to be injected at lower rpm levels for additional fuel economy gains. When the mixture enters the combustion chamber, the effects are cooler EGTs as well as added power. The total effect is determined by injection rate and percentage of methanol used in the solution. We don't plan to use greater than 15 percent methanol by volume because we're mainly after the EGT cooling effect of the product. However, even with just pure water, the Snow Performance kit can provide performance gains in the neighborhood of 25 to 30 hp. The total cooling effect can drop EGTs by up to 250 degrees as well.

We asked the good folks at Off Road Unlimited (ORU) in Burbank, California, to help us with the installation process. While they hadn't ever installed one of these systems before, they did comment on how complete the system was and how nice it was that everything needed, including flex-hose and fittings, were all included in the kit. Here you can see the 7-gallon reservoir ORU's guys installed in the bed. Snow Performance offers other tank options for those who don't want to hinder cargo capacity. The water/methanol fluid is available directly from Snow Performance or you can simply use any windshield wiper fluid that has methanol listed in the ingredients.

What About Reliability?
Diesel engines found in Duramax trucks have a built-in robustness that allows end users to increase horsepower and torque without sacrificing longevity. However, this is only true to a point. We questioned Steve Cole about our truck's power output, and whether or not we needed to express concern about reliability in this story. His response concluded with, "It all depends on how you drive it." With that being said, we must warn readers that the Duramax engine will likely stay alive for a good long time at 480 hp, though proper judgment should always be used when pulling heavy loads or while accelerating up long steep grades. Anything over 480 hp is pushing the limits of the design of the engine. The hot exhaust-gas temperatures generated by the additional fuel burning can cause pistons to melt, gaskets to fail, and damage to other engine internals. Upgrades like the ones we performed in this story are designed for those of us who don't mind sacri- ficing critical built-in safeguards for the ability to spank challengers at the track. Please realize these modifications are not recommended for emissions-regulated vehicles and are in no way going to increase engine or drivetrain life. The bottom line: The higher the horsepower, the less likely it's going to last 100,000 miles.

The Cost
We get reader requests all the time asking us to list prices of tech projects like this. So this time around we kept a running total to show you approximately how much green it would take to get it done.