injectors can only produce so much fuel period. E85 requires a sh1t load of fuel. On gas 60s at 58 base with a 1:1 is good for around 700 hp. I was also on a mustang dyno. My heads flow very well so does my intake and cam. I make my power NA with having a healthy setup.
if anyone planning to make power on E85 look into the FIC 95lb high impedence injectors. At 68 base they are 118lb injectors. just recently purchased these for 600