Over the past few days I along with local Preformance shop have been experimenting with different mixes( water, denatured alcohol, methinol, ethanol) in his 2009 TDI
We Have put approximately 6-7 gallons through the system and got a lot of positive results with a bunch of vareables. Along with injection times and boost psi and EGT.
My conclusion. For everyday running 40/60 1gal fuel to 1.5 water provided most consistent results. For long halls with or under a load 3 qts fuel 1.75 water gave best cooling and added lil power and great cooling. ( had same results with 50/50)
Even tryed some mixing of Methanol,denatured alcohol and isopropanol( rubbing alcohol)
Refrance this sight for explanation on what each does differently
http://www.alcoholinjectionsystems....r-Methanol-Injection-System/article_info.html
Had great results but is worked out to $26 a gal mixing the 3 alcohols with deionozied water. Split the Alcohols up into 3qts each mix together with 3 qts water( talk into account the % water in the isopropanol try to find 90% alcohol and use deionozied water.
There was no huge power change with the different fuels so price should be your driving Factor.
Also found setting my MPG ON at 11psi and 100% at 18 psi. Power mode on at 16psi helped not get too aggressive of a curve.
Hope this helps you guys.