I used a 4 X 8 tube cut a wedge out of each end to make it 4 inches at the ends. Looks decent and made a good air tank for the on board air.
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01,qcsb,fwd,he351-3b,adrenaline,pulse,200injectors,5in.stacks,5disk converter
02,qcsb,fwd,35-40,edge juice attitude,2.5mach injectors,4in.exhaust,4 disk converter,