My A-Spec 500R Kit Dyno Charts

[afterburn27]

Wow, that is pretty poor response from an 0.84 A/R housing. I would expect 15 psi closer to 4k RPM.

Your setup seems correct to me. Someone already mentioned it, but check to make sure you have the correct settings on your dip switches.

I would also expect better response off the wastegate alone, meaning that your EBC setup might not be a factor. Are you sure that you don't have any exhaust leaks on either side of the manifold? I had a friend with a similar situation and once he fixed his exhaust leak he was spooling 500+ RPM earlier than before. It was tricky too because you couldn't hear it at idle or cruise. It was really only leaking under boost and he had an open wastegate so there was no way to verify the leak until it started leaving carbon deposits under the manifold.