I have the LML drivers manifolds and tow flow up-pipes. I am wanting to upgrade to a compound set-up and add more fuel, but cannot decide on weather to go cast or log? Truck is just a DD, and use it on the interstate alot, but I want more...this thing is reliable and a blast but is a my main source of transportation. Please advise; RDL is having a 10% off sale; just want to take advantage of the situation.