it depends on how you setup the anti-lag or 2-step.
you MUST retard the timing for when the anti-lag engages. when i setup my friends AEM, i retarded the timing with 2-step engaged all the way down to 10*BTDC. i set the ignition cut at 4500 and the fuel cut at 4800rpm. with it set up like this, he can build anywhere from 10psi to 14psi on a ITS72mm w/ 0.86ar hotside depending on throttle angle. the exhaust note changes DRAMATICALLY when the ignition timing is properly altered for 2-step engagement.