Brief Description: Relocating the Heat Muff Flange
One of the little issues I have been putting off is the location of the heat muff flange. The original location is on the back side of the rear baffle on cylinder #3, per OP-54 drawing plans. BUT, this location is good for a heat muff that installs around the right exhaust only. My heat muff is installed on the cross-over just in front of cylinders #1 & #2. I dabbled with the idea of replacing the heat muff, but I don’t have the exhaust system that would allow that. All that brain cycles just trying to avoid the obvious, which is to simply relocate the existing flange to the correct location on the left forward ramp in front of cylinder #2.
Drilled out the four AD470 rivets for the existing flange. Used the flange to create the plug which I riveted in place using blind rivets and some RTV for good measure.
Located the holes for the flange on the left front ramp, located the center and drilled a #40 pilot hole, then drill to 1/4" for the 2" hole saw to center. Final drilled the 2" hole for the flange, then used the flange to match drill the #40, then #30 holes for new AD470 rivets.
Used more RTV on the flange, then riveted the flange to the front ramp.
