Are the airflow specs identical to the bushing 500s? I'm looking for a turbo that flows just a little more than stock (plan to run no more than 18 PSI) with as little lag as possible (hope to go with BB turbos with ported intake and exhaust manifolds with Greg's DPs and midpipes with hi-flow cats.... mmmm, no lag!). What do you think? Where do you think the boost would kick in on this setup (I also have Stillen intercoolers)?