Lately I am putting together one of the simplest and most consistant and tuneable water methanol injection systems any one has ever seen.
I have a steady local source of 80 proof water methanol. I ran some numbers and figured out that for constant spary I want no more than 3gph and no more than 10% alcohol.
DIY Water Mist Injection system install, w/pics (MPG Boost Project) - Page 27 - Diesel Place : Chevrolet and GMC Diesel Truck Forums
Go back a few pages for my water injection system pics.
Water injection - EcoModder
Built an intake adaptor to try and use what I believe is the more efficient of the 5 factory intake manifolds made for the 6.2L/6.5T engine serries.
The problem is that intake manifold is set up for N/A use and I am trying to run a turbo ready intake for testing.
F-code/J-code adaptor - Diesel Place : Chevrolet and GMC Diesel Truck Forums
I removed dirty stained 2nd row seats, 75lb.
And I bought some .100'' aluminum dimond plate to do a 7 inch air dam just below the bumper.
Edit: cancel that Idea, I'm putting a peterbilt bumper on.
And I have come to the conclusion I need to trade my brand new 31'' yokohama AT-S tires for some 31'' General LLR HT-S (highway tires).
Edit: I am going run all 5 of my yoko AT-S tires till they are smooth.
I am down 7mpg from my all time high. This is where I think I am losing MPGs:
Winter -2 to -3 mpg
Going from sea level to 4400ft, -1 to -2 MPG (nothing can fix that)
Going from worn 31inch good year RT-S tires to new yoko 31inch AT-S tires -2mpg (confirmed by friend who did the same swap)
Switching from my ram air fed J-code intake manifold to the turbo ready F-code intake manifold. -2mpg (didn't know what was going to happen when I did this)
Edit: I hand made an adaptor plate to put the pennsular upper plenum on a non turbo J-code intake.