Some fuel for the fire (I couldn't care either way as I went full ECU tune) but SXTH Element did an experiment the other night with their shop car to help settle a debate. Below are the results of that experiment.
Mods on the car: (essentially full bolt-on)
-SXTH intake
-SXTH Fmic kit
-SXTH catless downpipe
-SXTH cat-back with muff/res
-SXTH dual catch can system
Fuel was E30 for both.
First, Mark dyno'd the car with the stock ECU. As you can see, the power limiters in the stock ECU were showing us just how much they like to ruin the fun. If you want more power than this, you NEED some sort of solution outside the stock ECU. Be it in piggyback or full ECU tune form.
Next, he ran the Lap3 Pro Tuner on Mode 3 (pretty sure this requires E30). Very strong numbers for a piggyback, fantastic curve.
Here it is vs the stock ECU so you can see the difference:
Next was the AFE Scorcher on Race Mode. (AFE requires 93+ octane for this mode)
And Lap3 Pro Tuner vs AFE on the same plot. (Lap3 dotted lines, AFE solid lines)