2200 EGT Balance front to back
I have a 2200 which is showing EGTs on Cylinders 1&2 much higher than 3&4. I can move the balance left to right by turning the carb a bit but I have not been able to change the front to back balance. Climb out is fine at around 1200, however cruise at 2800-2950 has the 1&2 running at 1385 and 1335 while the 1&2 cylinders are barely at 1200. Should I be concerned about this and is there a fix? This is on a pusher configuration.
That's a difference worth looking at I'd say, if for no other reason than making sure the sensors are reading correctly.
The usual place to start looking would be to make sure there are no air leaks on any of the intake pipes - look for loose screws on flanges, cracks in the sealant, cracks in the rubber couplings etc.
Next, if it's a "naked" installation it would be worth trying to protect the intake pipes from slipstream effects - we've had issues before (mainly in cold climates) where slipstream air makes some of the intake pipes really cold, which condenses more fuel out of the air/fuel mix, throwing off air/fuel ratios on those cylinders. As a first try you can wrap those pipes in exhaust pipe lagging or similar and see if that makes any difference. There's also a possibility of a spurious reading from the EGT too, if the back end of some of the sensors are exposed to airflow.
There are various other tricks inside the manifold to change fwd/aft mix but they tend to be very fiddly and frustrating so I'd start with the external stuff.
I've check and swapped out the sensors and they appear to be ok. They are in the airflow on this Tornado II pusher but the hotest ones are in the back of the plane, closest to the prop but furthest from the carb. No apparent leaks and temps here are in the high 80s and 90s F.
At 2920 RPM #1 1309 #2 1334 #3 1131 #4 1183
At 2860 RPM #1 1389 #2 1346 #3 1241 #4 1197