I am in the process of changing my boat over to E-85 fuel. I have been running 91 octane pump gas. The engine is a 400 sbc with a 6-71 and an intercooler. I installed my new wideband O2 sensor today, and am going to do the carb and fuel line mods in the next couple of days.
My question is this.
Right now I am spinning an AA stainless impeller 5500 rpms and the boat is going 85-86 miles per hour at 7 lbs of boost.
I was told that with the E-85 that I could about double my boost safely. Does anybody have any general ideas of what kind of power is to be gained by doubling the boost? 20% more? 30% more? 50% more?