Hi Al,
I would confirm your experience. It will continue to run 200 LOP, but even at 100 LOP it is starting to have significant misses. Even 50-60 LOP has a much rougher feel than ROP, but the EGT's really start to fall off and fuel consumption drops.
I have noticed that much of the problem is rotor balance. If one rotor is 20 ROP, the other may be well LOP. If I carefully work to match the rotors then I run much smoother well LOP. The problem for me is that my rotor balance is very dependent on RPM. If I get them matched at 5000 RPM, then they are WAY different at 6000 RPM and vise versa. (evidence of a very poor manifold design?!)
For my next turbo destruction cycle, I plan to really focus on EGT (like cert engine pilots have to). I will balance the rotors at a particular RPM and only run LOP at that RPM. Otherwise, I will run ROP. If I can get the turbo to 500 hrs, that would be less than $2/hr and it would be worth it. Keep 2 turbos in cycle to the rebuild shop, and always the means to fly around n.a..... I'll let you know how it goes :-)
Dave Leonard
On Thu, Jun 26, 2008 at 7:25 PM, Al Gietzen <
ALVentures@cox.net> wrote:
How many hours are on your sparkplugs and are
you useing auto fuel or 100LL.........Something to
consider before a 2000 mile trip.........Could be
possible indication before the dreaded "SAG"..........
I don't recall (have to check the
engine log), but I'd guess maybe 20 hrs; only 10 ga 100LL; all the rest
unleaded mogas. I took a leading and trailing out yesterday to look at
them and they look fine.
Al
--------------
Original message from "Al Gietzen" <ALVentures@cox.net>:
--------------
I'm finding that at about
100F LOP I sense that the engine is starting to not like it – like it
doesn't seem to be entirely smooth; maybe an occasional miss here and
there. Am I right that some of you guys run as much as 200 LOP; or is it
my imagination – in both cases.
Would timing setting have much of
anything to do with running LOP?
Just past by the 100 hr mark on
the engine near the end of a 500 mile trip on Monday. I plan to leave
next Monday on a round trip of over 2000 nm over the following week.
That'll rack up a few hours.
Al