Quote:

Peak hp 520 at 5600
Peak tq 560 at 4500

You should be very happy with the results.

I was a little surprised the torque peak was that high (rpm).
The MP 0.528" cam is very mild and has good street manners, as you found it will go to 6000 rpm with headers, etc.

What size were the dyno headers? Maybe that raised the torque peak. I would guess the headers vs exhaust manifolds are around 30 hp.