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Header mock up

A great way to mock up headers for custom applications is to make semi-flexible ones out of 3/4” pipe insulation(36”) and 1/8” gas welding rod 36”(any stiff wire will do). For each cylinder take 2 3” pieces of keystock and weld them together parallel to each other with 3 1/4” x 20 nuts between them(one at each & one in the center) Cut the heads of some 1/4”x 20 bolts and weld them to one end of the rods with about an inch of thread extending off the rod. Bolt the rods onto the center nut of the keystock forming a “T”. Slip the rod into the pipe insulation and spiral wrap it with duct tape. Fill the pipe insulation from both ends an a few spots in the middle with “Great Stuff” urethane caulking. once its dry you can use the “T” end to bolt to your cylinder head and bend your dummy primaries to what ever configuration necessary to clear everything. They will hold their shape so you can remove one at a time and duplicate them in real tubing. Good luck! Smitty

Comments

erohslc:

A similar method uses spiral pool hose (Lowes/HomeDepot). Cut a piece of 1/4” plywood to make a fake header flange, then 1” long pieces of wooden dowel to tightly fit the inside of the hose, screwed to the plywood. The collector end is pieces of the dowel screwed to a scrap piece of the plywood. Cut equal lengths to your calculations, and number each hose on the ends. The hose maintains it's length, but is flexible enough to route as needed. A bit of Duct Tape, wire, or tie-wrap holds things in place, and then shoot in some foam when you get it the way you want. Disassemble, and make the cuts'n'bends. Carter
Jul 28, 2009 12:54 p.m.