So once again I did the 175 tune and lemme tell ya, its a freakin' B E A S T!!!!!!!!! from 20mph-105mph it was nothing but thick black smoke being dumped out the pipe! i was completely amazed at the amount of smoke it produced!!!!!! i literally "blacked out" a portion of US 41 for however far 20-105 took me. very smooth except for a "turbo chirp" but that is being worked on as we speak by casey