Hey duck, i put a dv on my daughters 04 grand cherokee with the 4L engine. Her increase was from just over 3 miles to the gallon on the initial run. we have not checked again since they are having problems with a leak in the hoses some where.
If you decide to get one... This is one thing I know for sure, YOU WILL DRIVE IT FASTER. Due to the perceived horsepower from the increase in air pressure.
Nobody ever talks about that... Is there a increase in horsepower from the Dynovalve?