With the fuel and mods Dustin has he could hit 30 PSI and keep on skipping higher with the S510. A lot of it has to do with the exhaust housing.
Mike knows more about my truck then i do sometimes LOL, he knows what housing and everything is on the turbo, it was his LOL
Im thinking a 60mm gate would by pass 4 whole cylinders, that would be enough to lightly drive the stock turbos... i think, might need more gate then that i dunno.