A slightly different setup as I'm currently on E30 with WMI instead of upgraded injectors/HPFP. My base run for E30M wouldn't be a good comparison to yours since it was based off of the finalized 91M tune running ~25 psi boost and ~300whp.
Below are the finalized tune graphs/numbers for three fuel types. Runs were on the same road during evenings for consistency. However, note that the process started going into the summer in the Phoenix metro area. It was around 70F when I started with the 91oct tune, and around 95F when I finished with the E30M tune, so I suspect 91M and E30M tunes would've shown higher numbers if the ambient temperature remained the same.
I went with Tune+ and Adam thought there was still around 5-10whp left to tap, but wasn't sure if it was worth the risk. I agreed since hard acceleration in 1st or 2nd gears were worthless as even on summer tires and certain 3rd gear pulls were starting to show signs of traction issues.
Best of luck! As
@MO15Fiesta mentioned above, I don't see why you can't hit at least 320whp given upgraded injectors and cooler temperature.
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