OK! Spent the day working in the cold cold barn, but I’ve got
some samples of bending exhaust tubing with a Greenlee 880 one
shot rigid conduit bender.
Using the 1 ½ “ shoe and pipe supports, which is the closest
match to the 1 7/8” tail pipe tubing, here are the results.
Made a 90° bend which you would use over the rear axle with a
45°bend in front and to the rear of it. The radius is larger
(8 ½” central radius) than it would be if it were done on a
commercial exhaust pipe bender. Although the 1 7/8” tubing
fits the shoe perfectly, without the support of a follower it
flattened the tube at the outer radius and wrinkled it at the
inner radius.
Using the same 1 ½” shoe and pipe supports on a 1 ½” EMT thin
wall the tube just folded after about 20° of bend.
I then switched to the 1 ¾” tubing die set to bend the 1 ½” EMT
that produced a near perfect 90° bend.
http://www.pbase.com/dennygraham/exhaust&page=all So, without a tubing die and follower sized for an actual 1 7/8”
OD tube you can’t make a satisfactory bend in that size tubing.
The same thing would apply to the 2” head pipe.
Denny G
