So, I just bought a 543...

My friend had his 543 dynod with stock unported 906's with a smallish cam 525hp and 625 lb-ft all in below 5,000 rpm.

Interesting--the big question for me is--How does it drive? As in--Does it RPM willingly up to and over 5000 rpm ? Or does it takes its time to get there kinda thing? Honestly asking with that 522 RB build I've got going on. J.Rob