JonJay
Well Known Member
While my #2 Cylinder was out for the repair of a sticking exhaust valve, I decided to rework my ramps and forward baffling. I was never happy with how they originally came out so it was a good excuse and time to fix it right.
I am now flying again with just over 6 hours on they new cylinder and was pleasantly surprised to find that my cylinder head temps have a maximum separation of 5 degree's in cruise. I used to see 10 to 20 degree's and never worried about it, nor would I worry about it regardless. However, I did not expect to see these kinds of results;
25"/2500
55F. OAT
1500' alt.
150 ROP
185F. OT
CHT#1 = 349
CHT#2 = 349
CHT#3 = 353
CHT#4 = 348
I also find it interesting that these temps held pretty true, +- a couple of degrees, at 48F-60F. OAT. I always thought that OAT and CHT had a direct linear corelation but my data seems to not follow that while it may be direct, it is not 1 for 1. Same for oil cooling. Maybe someone can explain that to me.
I also firmly believe that while specific engines perform in the same realm of operating temperatures, there are differences. Some identically equipped machines run hotter and some colder. Perhaps the little details make the difference or it is just built in. Just my observation.
I think as a group we get a bit hung up on our baffling systems. However, with a little attention to detail, you can really increase the performance of the system.
I consider my rework a success.
I am now flying again with just over 6 hours on they new cylinder and was pleasantly surprised to find that my cylinder head temps have a maximum separation of 5 degree's in cruise. I used to see 10 to 20 degree's and never worried about it, nor would I worry about it regardless. However, I did not expect to see these kinds of results;
25"/2500
55F. OAT
1500' alt.
150 ROP
185F. OT
CHT#1 = 349
CHT#2 = 349
CHT#3 = 353
CHT#4 = 348
I also find it interesting that these temps held pretty true, +- a couple of degrees, at 48F-60F. OAT. I always thought that OAT and CHT had a direct linear corelation but my data seems to not follow that while it may be direct, it is not 1 for 1. Same for oil cooling. Maybe someone can explain that to me.
I also firmly believe that while specific engines perform in the same realm of operating temperatures, there are differences. Some identically equipped machines run hotter and some colder. Perhaps the little details make the difference or it is just built in. Just my observation.
I think as a group we get a bit hung up on our baffling systems. However, with a little attention to detail, you can really increase the performance of the system.
I consider my rework a success.