Jerry Bass wrote:

HI, I got back into the air today. The new pipe is 2" from engine to a Y pipe that goes directly to the 3" out pipe. The total length is about 40 inches. halfway between the 31" and 47" on the diagram. I squashed the 3 to 5" megaphone to a Fish Mouth at 8" x.5" All 321 SS with the fishmouth 304 SS.

Now I get a strong 1200 fpm climb at 6600.  Full throttle at level is 155kts
[178 MPH] or better at 7500.  Noisy though.

Jerry Bass
540-932 3125
Cell 241-2675

Congratulations on that.
That is not a correct fish tail.  The exit area is only 1/2 by 8 or
four
square inches. The cross X area of your three inch pipe is 7 square
inches.
Your fish tail then should be 1/2 by 14 inches.

Something wrong. You should be doing over 200 MPH like Ian as you both
have
2.85:1 gear boxes and RV6A's. With more climb as well. In theory the
single 
pipes should be around 30 inches give or take a few. Perhaps your prop
has 
something to do with it.

Paul Lamar
 
The AirCraft Rotary Engine NewsLetter.  Powered by Linux.
ACRE NL web site. http://home.earthlink.net/~rotaryeng/            
Copyright 1998-2003 All world wide rights reserved.