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Bob.
Make sure that after repitching the prop your static RPM is within the
limits still.
48 pitch is a climb prop for C85's and O-200. But for a C-90 the 50 pitch
is listed as the lowest recommended .
(Where the heck did I read that??)
Reason for that is that the  C-85 and the O-200 are allowed to run faster
than the C-90.
They have to , because their additional power compared to the C-75 & C-90
they derived from, is developed with more rpm on these machines.
The C-90 on the other hand has a different power curve - more flat-
developing full power already on lower rpm. While repitching the prop to
more climb might get you faster of the ground, you might run into problems
when being up there and never be able to cruise at full power , because
you redline the engine all the time.

To say it again : a McCauley 1a90C7150 is already a climb prop on a Coupe
with a C-90 engine.
If you meet 2250 - 2375 rpm on run-up you are good, if not , fix the
engine.

If engine is good and weight seems to be a problem, consider taking off
with less fuel and refuel at a longer runway, when going on a trip.

But from my experience with taking off on a grass runway, I can only say
that besides weight, the condition of the grass and ground are having a
big influence on the performance.
On slightly drier ground , the takeoff is experienced much more
satisfying.

Hartmut


[EMAIL PROTECTED] wrote:

> ----[Please read http://ercoupers.com/disclaimer.htm before following
any advice in this forum.]----
>
> Thanks for all the replys.  Does anyone know what it cost to repitch a
CM7150 prop to a CM7148  This seems to be the most suggested possible
cause for my problem along with my fat ass and the tall grass.  I have a
lawn moiwer and will heed that advice and I know what weight watchers cost
.  Will have to think about that one.  I don't know if I like eating or
the coupe more ?????
> Bob Bullock
> N5621 1966 Alon A2
> Maryland
>
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