boom3

Well Known Member
Fixed Pitch / IO-360B1B / Vertical / 2 Mags

Cylinder #2 and #4 are the hotter of the bunch.

On a relatively short 2nd flight today, I'd tried to make a good graph of my question.

Already warmed up from my previous flight, I climbed to about 3000, leveled off, and reduced power. Shortly there after I began leaning to peak EGT, then flew for a bit approx 50 degrees LOP. Then I enrichened to 75 ROP and flew around a bit.

You can see the the large CHT spread, approx 25 deg, during takeoff and ROP operations. LOP yields a significantly smaller, approx 10 deg, spread. If my baffling was poor on #2 and #4 wouldn't the spread stay the same?

By the way I don't think my baffling is poor, but I guess it could be.
My EGTs peak about the same time.
Already checked timing, senders, etc.

chart.jpg
 
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Our #2 & #4 are hotter by a similar margin.

TMX-IO360 dual P-Mags, low curve, plenum, well sealed elsewhere.
 
25 or 30 degrees between cht's is quite good. It is very tough to get all the conditions the same for each cylinder - mixture, cooling air, etc.. If engine is new or rebuilt, don't worry. Just when you think you have it dialed in, it will change...

It is not simple to even determine if the readings are all accurate in flight.