FWIW, this is yet another clue that you had retarded timing on old
engine. The higher coolant temp is from more power and/or some
break-in friction but main thing is the lower EGT, which is a BIG
indicator of more ignition advance (a good thing until you get to detonation
point).
The other thing you have mentioned is the exhaust note. Retarded
ignition will have a deeper tone (many would think it better) but healthy
ignition advance will have a sharper edge to exhaust note and less 'bottom
end'. Your exhaust always sounded 'bottom heavy' to me.
Lynn's comments on ignition advance matches what I have experienced.
At anything below 22" MAP, the advance can run as much as 30 deg BTDC. At
my typical cruise MAP is around 17-18" Hg where advance runs 32-33
BTDC.
Tracy
That's interesting, Rusty
I have noticed that my coolant temp is up and my EGT is down (about 100 -
150F) over the old engine. I am speculating that the rise in coolant
temp and decrease in EGT MAY be due to better combustion (less blow-by of gas
into the exhaust) - but a little early to tell. Once the engine has
about 10 flying hours on it, the status should stabilize. The coolant
temp has come down about 5 -10F over what it was when I initially fired up the
engine.
I hate to think that much heat increase is due to the friction of
breaking in all the seals. I am trying something different this time, I
am breaking the engine in using Mobile 1 Synthetic oil rather than the mineral
oil as I did previously.
Went to auto store to see if I could find a S&B filter - they once
had them, but had stopped carrying them. Claimed they were good
filters. Was going to check for me and see if anyone else in the local
area carried them. Might just end up with a K&N as they are probably
easier to find almost anywhere. But, I liked the funnel shaped inlet to
the TB that the S&B had and the K&N did not. Got to get that
filter on before Leon gets on my case {:>)
Hope your water is going down
Ed