I have been planning on starting the break-in on the ground for many years. Now that I have actually experience doing it, I thought I would post this for anyone else thinking the same.
It was fairly simple to build. The hardest part is making the scalloped tabs that bend over and rivet to the top skin. Used the old ECi overhaul crews recommendation of 1 cubic foot of inlet area for each cylinder. The cable in the center I think now is overkill, but didn't want to take any chances. When bolted on it is rock solid.
Did my first break-in ground run this morning, 50 minutes 80% power. The shroud worked well, with the highest CHT htting 330 deg. I need to increase the size of the oil cooler inlet some as the oil max'd out at 250 deg. I used an extra Van's eyeball vent rear end and thought it may be too small, but wasn't sure how much pressure I was going to get.
I know there are those out there who like all the technical data, like me, (no offense Dan ) , but we are trying to get this plane to Oshkosh, so I am sorry there is no time to try and modify my engine plenum press box to take readings. If I have time after Mel has given the plane his OK, may try and get pressure data, because I would like to know. On the other hand there is the old, "it just works" way of thinking.
It was fairly simple to build. The hardest part is making the scalloped tabs that bend over and rivet to the top skin. Used the old ECi overhaul crews recommendation of 1 cubic foot of inlet area for each cylinder. The cable in the center I think now is overkill, but didn't want to take any chances. When bolted on it is rock solid.
Did my first break-in ground run this morning, 50 minutes 80% power. The shroud worked well, with the highest CHT htting 330 deg. I need to increase the size of the oil cooler inlet some as the oil max'd out at 250 deg. I used an extra Van's eyeball vent rear end and thought it may be too small, but wasn't sure how much pressure I was going to get.
I know there are those out there who like all the technical data, like me, (no offense Dan ) , but we are trying to get this plane to Oshkosh, so I am sorry there is no time to try and modify my engine plenum press box to take readings. If I have time after Mel has given the plane his OK, may try and get pressure data, because I would like to know. On the other hand there is the old, "it just works" way of thinking.
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