I have a 2015 fiesta st w/ upgraded intercooler,downpipe,exhaust,intake,rmm, bov, and the Cobb stg 3 tune. I've been looking at the ATP GTX2860R and also the x37 & the DHM kit but the atp and DHM both run garret turbos...right?(well the DHM it comes with the extras but cost double) I honestly plan on getting it to 300hp(350hp at most) but I'm in LA so I'm restricted to only 91 oct. and I'm also very very confused lol I've been also reading that the ATP GTX2860R can't run to the full potential do to restrictive fuel and have seen they have the auex fuel kit.....but how will that do with 91 oct? And of course when I get the turbo installed I plan on getting a tune with it. Any help would help and what my best options might be to run 300hp on 91oct. Thanks!