Starting the de-bugging

Now that I proved that it can fly, I need to get after all the squawks. Right now, the main issues are engine heat and power. Yesterday I went out and:

1. Adjusted elevator push rod for better roll trim.
2. Significantly opened up the path for cowling discharge air.
3. Discovered air leak around #2 cylinder. Will repair after next test flight.
4. Took care of fuel line chafing on cowl.
5. Plumbed in an airspeed indicator to measure cowling pressure differential.
6. Hooked up mixture meter so I can observe it in flight. I will continually be checking the fuel/air ration to fine tune the EC3 mixture mapping.
   

It started raining so I didn't fly.

Regarding item # 5 above. There are a lot of factors about engine cooling and there are several great articles out there if you are willing to search for them.

One of the fundamental things to check for is to make sure that you have an adequate pressure differential between the top of the engine, compared to the bottom of the engine. The engineers like to refer to this as inches of water, as seen in a manometer. Let's say you had no baffling at all. In that case there would be zero pressure differential and zero inches of water.

Lycoming wants to see between 5 1/2 & 6 1/2 inches of water. Since rigging up a manometer can be cumbersome, there is an easier way, using an airspeed indicator. I had an old one laying around so I hooked it up kind of like this (scroll down a bit).

If I don't have enough pressure differential, that should be addressed first. But, if there is enough difference, then I need to go after different things like controlling air flow around a specific component, but first things first.

So looking at the table below, I will be hoping to get about 110 mph on the indicator.

MPH	KNOTS	IN. of H2O	#/IN2
30	26.1	.44	.016
40	34.8	.79	.028
50	43.5	1.23	.044
60	52.2	1.77	.064
70	60.9	2.41	.087
80	69.6	3.15	.114
90	78.3	3.99	.144
100	87.0	4.92	.178
110	95.7	5.95	.215
120	104.3	7.09	.2558

I'll report my results later.