if you want to tone it down put 2 base gaskets or 1 thick one under barrell
or you can run 2 head gaskets
i left mine standard but i am a sick puppy
main diff on barrells is exh port lower on IT
but remember the old IT465 went hard too
if you want too take snap out of it without loosing power
fit the IT boost bottle (remember them) ha ha
or just change up a gear