Greetings,
Here's my log from today. I'm not
too optimistic that the next climb will be all that
great.
Rusty (turbo
depression)
9-16-03
I tuned the engine today, after setting the timing to the
correct point. It’s now running
well on both controllers. Idle is
16-17 inches of vacuum (13-14 MAP).
I had to cut the fuel injector flow down by 4-5 steps to get in range,
which seems odd, but maybe it makes sense to someone. I set the staging point to about 19-20
inches MAP (12 inches vacuum on the gauge, which I know to actually be 10-11
because the gauge is crap). The
staging transition is still ugly, and will continue to be that way until I get
matching injectors. I had to make
the staging point a bit on the rich side to keep it from surging. Once I got done with the A controller, I
copied A to B, and then had to touch up the mixture just a bit across the
board. It’s obvious that the copy
function is working, because the ugly transition is certainly where it should
be. I ran as high as 7 psi of boost briefly,
and it really seemed strong, which is more than I can say for 0 psi. I’m going to be surprised if I picked up
any significant performance with the timing change.
FWIW, the rpm at 30 inches MAP was 5000 static. I’m pretty sure that’s partially stalled
though, so it’s worthless if it is.
If it happens to be correct, then it will be an increase in power. Only a climb will tell.
As a side note, the oil and water were both great during
all the ground running. Water
stayed rock solid on 180, and oil made it to maybe 190. This is running the absolute snot out of
the engine under boost.
Unfortunately, I’m still thinking that it will take about
5 psi to get the engine back to what a healthy NA engine would run. That means I’d have to run that on climb
from sea level, and run as much as 11 psi to get the amount of normalization
that I want. This is more boost
than I will be comfortable running, so if the next climb doesn’t change my mind,
I’ll probably start working on removing the turbo. 190 HP is plenty for an RV-3, and if I
really feel the need to optimize climb and cruise, I’ll have to come up with a
variable pitch prop.