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High CHT's On Climb

Yes, I do, and I increased the height of it - with no obvious effect,
Thanks for asking.
CHTs are pretty even in climb. The disparity becomes evident above 170mph indicated. power setting does not affect it unless I pull the power way back, to the point the other three CHTs start dropping.

Check for casting flash in the fins of the heads, particularly in the 3 hotter cylinders. Very common. To see if it is flash or not, compare to the other cylinders in the same spots.
https://www.youtube.com/watch?v=V-7Z4oOMSYI
 
I think I finally got mine under control.
1) Installed ramps in upper cowl.
2) Installed "bump" on lower firewall
3) Discarded trapeze exhaust hanger system devised by builder, and went with the tubing and hose hangers per plans.
Now, CHTs on climb run 375 or less, 325 to 350 in cruise - except #1 runs around 300??

Ramps, bumps and hangers.
I am a new owner
Can some post some pictures?
 
Post pictures? That's a bit above my technolevel.
Just kidding, but I don't have any of what I did to share. Next time the cowl is off, I'll try to remember.
 
let me help

so the ramp is the fiberglass piece that smooths the cooling air inlet to the top of the cowl on the inside.

The bump is the radius piece on the lower firewall cowl exit so the cooling air takes the turn from the inner cowl to the outside air around a smooth bend, and not the sharp 90 degree from the firewall to the lower fuselage skin.

hangars are the exhaust pipe hangars, not sure how this affects cooling airflow.
 
hangars are the exhaust pipe hangars, not sure how this affects cooling airflow.
So, probably only significant on my airplane, since it had a homebrew hanger system. It was a 1/8 x 1 1/2 aluminum flat bar that spanned the center area between the four exhaust pipes, tying them all together. Then, a strap from the center of that went up to anchor to the engine case. This effectively blocked 30% of the outflow area, and diverted flow toward the lower firewall/bottom skin lip.
 
Model #

Thanks Al for the reply, unfortunately I do not have a fuel flow indicator. Makes it a little tougher to figure things out.
Would you mind sharing which carb you got?

For my 0320 160 hp.

MSA 10-3678-32-H
 
I see cht reaching 450 on climbout on a not super hot day, ~80F at WOT, on Cyl 1 & 3. I am going to check for leaks and the airseals and try reducing power during climb sooner. I already have one antisplataero cowl flap on the right side bottom of the cowling but that seemed to be ineffective at reducing the max temp.
I put the boroscope in to look at the seals around cyl 1 and 3 with cowl on, behind cyl 3 this segment is kinked downward, and maybe isn't sealing from airflow.
fBnZfZe.jpg
 
I put the boroscope in to look at the seals around cyl 1 and 3 with cowl on, behind cyl 3 this segment is kinked downward, and maybe isn't sealing from airflow.


Look for dust streaks on the upper cowling. You should see black rubber rub marks where the baffles are sealing. What you don't want to see is a gap in the rub mark and a dust streak.
 
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