Update on the X57RS and tuning on 93 octane. I was recently getting negative corrections on my 4th revision. My tuner said that I should look into the usual stuff; plugs, boost hoses, and motor mounts loose. Long story short I gapped plugs to recommend spec, check all bolts/clamps, replaced coil packs, replaced PSMM, and figured out in the end it was poor fuel quality. My area has low quality fuel so I'm now mixing it with .75 of a gallon of e85 to keep a e10~e15 mix for my 93 octane tune. All negative corrections are gone or minimal under -.3 and very sporadic compared to before. Car is running great and I need stickier tires. Hopefully this is the final 93 revision for ~280 to ~290 Hp.