what is the best type of DUMP VALVE TO FIT.

Does it alter the engine response any or is it just a noise thing :?: [/color:128106fcfc][/size:128106fcfc]

You could write a book on these things, check out Forge, impossible performance, AMD etc. in the links section. Basically there are two types, the recirculatingn type and the whoosh type. All explained in great detail at the above sites. Also look at the FAQ section in Community.