Auto Racing: ehaust pipe size, size pipes, exhaust muffler

Question
i was wondering which size pipes i should go with on my 5.0 307 chevelle engine.

would 3"+ be to big, or do i need something smaller? would i need to upgrade the manifold and headers along with the bigger pipes?

additionally, do you have any clue as to what a true dual exhaust with 3" (or whatever size) pipes would cost?

Answer
Richard-

  Well, as a general rule, anything over 2 1/2" is really too big for anything under 325-350hp.  Will it absolutely kill your motor to go with 3" pipes?  No.  But 2 1/2" pipes would probably work better, cost less, and improve ground clearance.  Either way you go, there won't be any need to change the exhaust manifolds.  An exhaust (muffler) shop can set everything up with what you have now.  As far as price goes...I'm not even going there.  Even in a given town prices can vary significantly depending on the amount of piping needed, manpower to install it, even down to the type of steel the piping is made of.  It shouldn't be too expensive, though.