Quote: "should be able to run 12:1 or 12.5:1 a/f under boost."
I suggest running it no more than 12:1 a/f under boost.
Herb's old turbochargers book has interesting charts for a/f when using water. I'm pretty sure booster (Jim) uses 12.5:1 on his map through 15psi with his water on his 340. My combo is not that scienced out however.
