Okay........I pulled my DA-50 from EF Yak and it was running like a top on a stock muffler. I put it in an EF Extra with a tuned pipe (MTW RE2).

I started it today for the first time and let it idle for about 4 minutes per DA's instructions to seat the teflon coupler between the header and pipe. All was well. I loaded the plane up and headed for the field. When I got to the field the engine would not run more than a couple of seconds at a time and then would die I went all around with the needles trying to get it to run. I got it to run up a little one time but it had no top end (bogging very bad and would not come up) When I transitioned back to the low end it ran until I shut it off to lean the top end. I tried to reset both needles to 1.5 turns out and put a new plug in it with no with no results. When I got home I took the regulator switch and Lion battery out of the picture and bypassed them by hooking a NiMh battery straight to the ignition to make sure it was not any of that. It would hit on choke just like normal. I would turn the choke off and it would start and run for a burst and shut off. The weird thing about the whole thing was sometimes it would start and run for a second or two and then almost like backfire and then run backward.

Gap between header and pipe was set at 1/8th inch per Bill at DA.


Any help would really be appreciated.
Thanks
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