J-pipes new to me

[oldguy668]

All my other builds had FFR headers and my usual procedure was to mock up the headers and sidepipes before the body. That way, I could get them parallel to the frame and on the same plane. Since I'm using J-pipes on this one, is there any point to trying to mock up the system before the body?

[cgundermann]

With the J-Pipes you have the ability to adjust to ensure the side-pipes are straight. I have monkeyed around with the J-Pipes and side exhuaust after they were ceramic coated and found it easier to sure them up - using the bare frame as a leveling reference. Once you have them exactly true, you can make some reference scribes or mount the exhaust support brackets to the frame. Once the body is on, you can pivot from the hangers to ensure they are parallel to the ground.

[Jeff Kleiner]

Joe,
I always wait to do the adjustment of the pipes until the body is installed with the doors fitted. If your 289 body is like the Mk3 and Mk4 it will need to be pushed in at the front of the doors and pulled outward at the rear (especially on the driver's side) to get the doors to fit. Ultimately what this means is that the side of the body is not parallel with the chassis so therefore if the pipes match the chassis they won't match the body.

Jeff

[oldguy668]

Jeff, when Mike Everson and I mocked up the body we found that we had to do just what you said. We slotted the mounting holes on the body and then I drilled some cleco holes as locators before I took it off for bodywork. I think the difference front-to-back was about 1/2", so I guess I'll wait for final fitup to set up the pipes. I did bolt up the j-pipes last night and the flanges seem to be right in the ballpark so I'm not anticipating any major issues.

[Erik W. Treves]

I would wait until the body goes on for the 289 body. I had to cut back the body quite a bit to get pipe to lay parallel on the drivers side. Specifically the part of the body that rolls under the chassis in front of the foot box.

[BEAR-AvHistory]

As a first timer found it pretty easy to align the side pipes with J-Pipes after the body was on. Supported them with insulated bungee cords during Go Cart.

[oldguy668]

I would wait until the body goes on for the 289 body. I had to cut back the body quite a bit to get pipe to lay parallel on the drivers side. Specifically the part of the body that rolls under the chassis in front of the foot box.

The next time I see the body it will be painted, so there might be some welding in my future.

[skullandbones]

The next time I see the body it will be painted, so there might be some welding in my future.

oldguy,

I was considering the J-pipes at one time. It really freed up my anxiety about them after I thought how easy it would be to mount the headers and mount the side pipes perfectly and then if I had to to cut the J-pipes and have them welded in perfectly to match the other components (being able to remove and work on a bench after a little tacking in place). I think you are golden on this one! Not all the solutions on these things are this nice.

Good luck,

WEK.