i know julios 225tt spiked at 24psi and held at 20-21psi, my 1.8t spiked at 21psi and held at 17-19psi... it isn't that they run more psi to make power it is the tune they are running. i ran multi programs on my 1.8t and race ran maybe 1 more psi which wasn't much at all but the tune made like 10-15whp/20-25lbs more... GIAC just runs a more aggressive tune.Originally Posted by DavidTB8889