So I've got this crank and rods, was told it was a "383" crank, it looks to be a cast crank but how do I tell if its actually a 400 crank or if I got ripped off and it's actually a 350 crank, it fits in the journals of my 350 block so if its a 400 the mains have been turned down already to fit. How do I I.d. What the crank actually is? The rods I got with it measure around 5.5 center to center so I'm guessin they're 400 rods. Any help please?