I talked with Larry Vetterman about best places for the EGT probes in the exhaust pipes. There was a lot of information online about making sure the probes all sit the same distance from the exhaust flange and not to let them interfere with the spark plugs but nothing about what clock position around the pipe to install the probe. Larry gave me some good information to start with, one idea he had was to use a hose clamp to see where things set and or interfered. I drilled a hole in the scrap clamp so that the hole was in the same relation from the probe and the screw drive. I pushed a nail through the hole, this represents the distance the probe sticks out from the clamp, and I added a scrap inflation fitting to simulate the thickness for the probe. Now I could move the thing around and see where the best spot for the probe would be. I also had the spark plug socket and extension to test out positions. I then marked the clamp and pipe, removed the nail and reinstalled the clamp lined up with the mark I made between the clamp and pipe, and then used the nail hole to mark the pipe for the probe location; I will drill these holes once I take the pipes off.
For me with the cross over exhaust on the IO-360 these are the approximate positions for the probes, all 2” from the flange. The 2” down from the flange is set by the fact you can’t really get any lower due to the slip connector of the pipes.
#1 – 12 O’clock for the most part you want is perpendicular to the curve of the pipe #2 – 6-7 O’clock, I hedged to 6 to keep it from the cowl sides #3 – 4-6 or 7-8 works I chose 7 since I had room on the inside. #4 – 6 O’clock works here for me but any place on the aft side of the pipe should work.
