Pipe Bending Question

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Feb 21, 2006 | 09:59 PM

Motoshrump

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From: Saint John, New Brunswick

Pipe Bending Question

I am about to install a complete exhaust system on my 93 F150 302 2wd. Headers (Long tube) flowmaster Delta Flow 40 series single in single out swept out the side in front of the passenger rear tire. Anyways, I have 2.5" pipe for my soon to be y-pipe. I have access to a portable bender (mechanical hydraulic) which is capable of handling the 2.5" pipe. My question is when I bend the pipe where is the best spot to place the seam? On the inside or outside of the bend or perhaps another place? Any help on this would be appreciated. Oh, the pipe is of a good construction quality with a solid heavy wall (A good 16th of an inch). Thanks in advance.

Feb 22, 2006 | 06:46 AM

4.9inline6

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i would GUESS to put the seam on the edge. if you put it on the back or front, the stretching or shrinking might be kind of hard on it...thats my thoughts.
chris

Feb 22, 2006 | 09:52 AM

nick88f150

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From: fremont ohio

I would have to say aim it straight up in the air. I'm taking tool and die, and we just happen to be learning abt bending rightnow. When a peice of metal is bent, the inside of the bend radius is under compression, whilethe outside is under tension. Somewhere towards the middle, they have to balance out. It's usually just past the middle to the inside of the radius. The metal undergoes the least amount of pushes and pulls there. So I would have to go with putting the seamin the middle, aimed straight up. Someone else may have a better answer, we were talkin in class about the effects of bends on solid metal, not pipe, so I'm not sure if its the same principles or not.

Last edited by nick88f150; Feb 22, 2006 at 09:57 AM.

Feb 22, 2006 | 02:53 PM

Motoshrump

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From: Saint John, New Brunswick

I can see the logic behind that. Now that you mention it, nick88, it would appear that there is less distortion to the pipe at the top/bottom slightly towards the inside of the bend (depending on the angle) I have a little bit extra pipe so I'll try a couple test bends for cheap insurance. Thanks guys.

Feb 22, 2006 | 09:27 PM

kens64

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From: Rio Rancho USA

I agree with nick. Put as little stress as possible on the seam, so it lasts. IMO, I would use something without a seam, but since you already have it, go for it. If nothing else, add a weld bead to the seam to strengthen it.

Feb 25, 2006 | 04:37 PM

nick88f150

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From: fremont ohio

You try bending any pipe yet?

Mar 2, 2006 | 03:22 PM

Motoshrump

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From: Saint John, New Brunswick

Nah, the three inch was just too much of a hassle and I only have a few feet so I took it to the muffler shop so that they could deal with it. They spent a couple hours on it, ran everything perfectly, no clearance issues , I am very happy. With the long tube headers the collectors are so far back that they were next to the transmission pan. We had to run the drivers side front pipe down past the tranny and under the driveshaft yoke. This is one awesome exhaust, I recommend it to any one that wants a truck to sound like an early 90's mustang HO (with flowmasters of course). It provides a nice crisp throttle response, excellent low end torque due to plenty of scavenging and the simplicity of a single exhaust. This system works better than I ever expected.