Ed;

Seems like a misnomer to call this a 'light weight' manifold; but then
that's just me - my 20B manifold weighs only 2 1/2 lbs.  (Just had to
get that in :)

I can't help but think how very much lighter and stronger the part

would

snip>
Just my thoughts.  I guess this may be a quicker/easier way to go to

get

something done to see if it works.

Al

Are you including the weight of the TWM throttle bodies and
fuel injector holders Al?

Of course not.  The TWM TB is weigh heavy; ways considerably more than
the manifold.

Your manifold is a fine example of the hand made artistry of a
highly skilled tig welder. A good tig welder can weld .035 thick

aluminum.

My guess he worked on fabricating it for at least 16 to 20 hours.

Actually it is .058 wall, but you're right; a very skilled welder did
the work, and with cutting and forming the tubes spent about double your
estimate.

Too bad you are only getting 86 HP per rotor at 7000 RPM :)

Please - it is 86 /rotor at 6000, 93 /rotor at 7000.  And I guess I
should say that I'm not entertaining any discussion on the subject until
I see some actual dyno data on a stock NA rotary engine in an aircraft
that does better.  The only data I have on a similar engine with a
"tuned" manifold is the data on the all aluminum 4-rotor, which mine
beats by a couple of hp /rotor.  That, of course, is not to say that
some other intake manifold configuration may not be a few percent
better, I think it should be.

Al

The four rotor engine you speak of was also built by the same guy
that built your manifold. Here is a picture of that engine. It has the 
same "Y" in the manifold runners.

The Mazda  Lemans four rotor with the tuned intake is 120 HP per rotor at 6000 RPM.
Here is a HP curve on that four rotor engine.

Wow! At $50 an hour that manifold cost you a bunch. 32 to 40 hours is
$1600 to $2000. I hope he was working at day labor rates :) 
Not including the pricey TWO stuff. It is easy to make things
light weight if money is no object.

Paul Lamar
 
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