Fuel injectors

[redneck ricer]

hey its me again. first off im lookin into fuel injectors, more important im looking into the low impedance 550cc peak and hold injectors. from what i read, the nippon denso made some low impedance 550cc injectors that are a direct fit into the fuel rail of the MKIII. part number is 195500-1370. MY question is: will these injector require wire splice/soldering or anything like that? and what sort of performancre gain would i get on a stock supra..would it be neccesary to upgrade the fuel rail or fuel regulator before installing these injectors? and what would the maxboost i could run before fuel cut?thanks.