Ira, I thought along similar lines and ended up cutting the end obliquely
off my exhaust pipe, and angling it back a bit, modelling it on one of the
earlier company planes which is widely pictured. It saved an ounce or two in
weight,I cannot say whether it has helped it go fast (altough it certainly
does that) but it definitely has (1) produced a sharper edge to cut the
unwary head returning from looking up the engine compartment skirt, and (2)
led to a tendency to stain the fuselage a nicotine like colour which seems
quite a bit more marked than my contemporaries with untrimmed pipes! As I
have a gel coat finish I can get this muck off from time to time with
acetone, but guess it might be a real pain with standard paint finishes. Of
course it may be unrelated to the exhaust and simply indicate that the carbs
need tuning, but I doubt it. David Joyce----- Original Message -----
From: <irampil@notes.cc.sunysb.edu>
Subject: Europa-List: Exhaust Departure Angle
>
>
> Greetings All,
>
> I recently enjoyed reading Ken Paser's "Economy with Speed".
> It is essentially a study of the effects of applying 30-70 year old known
> aeronautical design best practices (from NACA reports) to the improvement
> of a modern homebuilt. The results is a much awarded and honored
> Busby Mustang 20 or 30 mph faster than others of its design.
>
> One technique involves canting the muffler discharge into the axis of
> flight to both mitigate the drag of the exhaust plume and simultaneously
> gain a small amount of thrust.
>
> Has anyone experimented with the Europa's exhaust? Best angle, etc?
> I know you donj't want to go straight back to avoid melting or staining
the
> fuselage.
> Andy? Neville? Graham?
>
>
> Regards,
>
> Ira N224XS
> Panel in and Fired Up
> Off the to Painters Soon :-)
>
>
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