white91gt, I really don't think you have anything to worry about, there are a LOT of mustangs running around with 255lph pumps with no problems and worst case if you do have an issue you can tie in a bigger relay and fuse and use the stock signal wire to control it. But I'ld say odds are you will be just fine on the stock stuff. 
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92GT Lowered with Ebiach's and Koni's, Kenny Brown subframe connectors, lower G-brace and jacking rails. BBK upper and lower control arms, polyurethane bushings all around and Ken Bell blower, ram-air, 80mm mass air, SMC Alky Injection kit, J&S Knock Gaurd, TwEECer RT and a bunch of other stuff!
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