http://www.bowtecharchery.com/downlo...nersManual.pdf
That 320-328 IBO rating is with a 30" draw length. Your bow is set up at 28", with an N3 module I assume. My birth cert stated 311fps @ 70.5#, 350G arrow, and 29" d/l. I'd say your certificate is right on and will probably increase to between 312-320 fps with a 29" module. It's odd that you took it home with the wrong module since most dealers I've talked to have the integer numbered modules in hand. It's the 1/2 inchers that seem hard to get.
My bad......I see that he did in fact change the module for you. You're shooting an N2 module now, correct?