2/11/2017. The exhaust system. Using Rhino3D, I designed a side exhaust system that I thought I could fabricate. I wanted the pipes at they came around the corner to angle up so they wouldn’t hang so low on the side. Hedman makes a nice shorty small block header with .375-inch flanges. They came with 2.5-inch collectors. Hedman makes 3-inch collectors that were ordered. Ordered from Summit were 3-inch mandrel bent “L” pipes, 3- to 3.5-inch adapter, 3.5″ mandrel bent “U” pipes, and one 4-foot 3.5″ pipe. Sweet Thunder 2.25-inch, 29-inch long inserts and Patriot turnouts completed the system. The 3D model helped me to confirm that cutting the “U” pipe at 45-degree angles would enable me to adjust the fit until it was right. After cutting the pipes, I supported them with stands and attached them temporarily with magnets. After getting them aligned, I tacked them together, and later had them properly welded. I’m not a welder. I left a slip connector one one of the joints under the car so I could adjust the in-and-out of the side exhaust.