http://www.roadraceengineering.com/fuelpumpflowrates.htm
Probably not I know if you re amp the 255 it will potentially flow more but with 12.5-14 volts it shouldn’t have any trouble.
Many DSM’s are plauged with “Phantom Knock” you may potentially be a bit too rich with the 1000cc injectors, which will cause a very hard to discover knock, get a wideband on it and lean it out untill it starts to disappear. Trust me your not the only one fighting your car tooth and nail.