Was watching American Thunder show an Edelbrock build last night. When it was all done, they threw on a pro-pipe and got 103 HP and 98 Torque. Then they changed out the Pro-pipe for VH true-duals and oval slip-ons and went to 93 HP and 91 torque. I knew pipes made a difference, but I was surprised to see that much of one. Bike was an 05 Road King Classic and they were tuning with a SERT.