Exit Fairing Results!
Ok, first off again let me apologize for the tardy posting of the exit fairing results. I know this has been a 'Hot' thread with lots of anticipation.
I have a solid database from test flights before I overhauled my #2 cylinder, but I flew the exit fairing test run after the overhaul. The test flight did not produce the results I expected, so I thought it best to take another day to do a test flight without the fairing to ensure my baseline numbers were still accurate.
BLUF: (Bottom Line Up Front) My goal for the exhaust fairing was never speed, any speed gain was a bonus. My goal was to smooth the exit air, increasing the cooling flow and lower my CHTs.
I am open for questions regarding my test data or flight procedures. I try to keep as many perimeters the same as humanly possible. Nothing is perfect, but I think I have a solid base to make decisions with. All test flight profiles are flown exactly the same.
(FYI: 24/2400 numbers are climb numbers, all other MP/RPM is level flight cruise numbers)
Here is the the Baseline data: (
WITHOUT Fairing!)
Here is the fairing data: (TWO test flights with Fairing
ON!)
Fairing performance numbers: (Numbers in
RED = Fairing produced
BAD results / Numbers in
GREEN = Fairing produced
GOOD results!)
Results:
CHT: Overall average 13 degrees HOTTER. Climb CHT increase average: 14 degrees. Cruise CHT increase average: 12 degrees.
(WITH fairing, 1st cylinder hit 400 degrees at 1min 50 sec into flight. WITHOUT fairing after 9 min 50 sec hottest cylinder was at 392 deg.)
EGT: Overal average 16 degrees HOTTER. Climb EGT
decrease average: 24 degrees. Cruise EGT increase average: 30 degrees.
Fuel: Rate of burn (Both climb and cruise) increased by almost 0.5gph.
As for the speed respect of the fairing, I would not take my opinion in choosing to add the fairing. I did not fly the 'speed profile' that is described in the forums using 3 or 4 legs and TAS etc. The speed data on my forms is strictly IAS and GS for my own kicks!
I would like to take the standard "5-7mph gain" that comes with any speed modification, but my opinion is there wasn't any noticeable speed increase.
There it is guys. I hope others have better luck with the fairing. It has worked great for Gary. I think the fact that I have an "A" model with anything and everything blocking the exit and causing massive exit flow turbulence has a lot to do with exit flow performance.
JMHO
Dan