99 to 04 GT's put down about 210 to 220 to the wheels. WRX's put down about 170. The 300 lb advantage for the WRX isn't enough to overcome that power deficit. A stock WRX would be ahead for a little bit due to awd, but after that it would be a while till they evened out based on gearing. From a 10 to 30 roll start, the GT is going to win hands down.