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"We went from 376 in 1998 to 446 in 2009 using 2 stock motors from Aircraft Cylinder."
What aero mod produced the largest single gain?
Thanks, Kevin
The paint and airframe profiling gave us the most followed closely by the smaller canopy and windscreen. Both took months to complete but were well worth the effort.
Ray
Bill,
You are correct, on a stock motor the slow speed nose case won't help. We had tuned our motor to run what the Wright 3350 manual had specified as METO power. Alot of work was done with the carb jets and fuel flow as well as ADI settings. The most speed we gained was from drag reduction i.e. exhaust pipe angles, custom canopy and windscreen, gear door adjusments, wing and fuselage profiling. Kerch was a huge help with this. He sent me an engineering study done by Hawker in the late 40's. They were trying to break the world speed record for a prop plane and were looking at airframe modifications. It showed each mod and the amount of speed that was gained. We went from 376 in 1998 to 446 in 2009 using 2 stock motors from Aircraft Cylinder. Our crew cheif Jim Skinner did the best he could with the plane considering Mike also used the airplane for airshows and cross country flights.
Ray
You wouldn't still happen to have that study would you? I'd love to read through that.
Mostly it is the blower that makes the HP difference.
Gotcha, but if some teams have gained an advantage by using the slow nose case, it would stand to reason that they were also running higher than stock max rpm. I'm just curious what fails first when a 3350 is pushed to higher rpm?
Gotcha, but if some teams have gained an advantage by using the slow nose case, it would stand to reason that they were also running higher than stock max rpm. I'm just curious what fails first when a 3350 is pushed to higher rpm?
This is just from observations over the years from a race fan in the pits. It always seemed like when something went wrong they started swapping jugs. Torched pistons?
Gotcha, but if some teams have gained an advantage by using the slow nose case, it would stand to reason that they were also running higher than stock max rpm. I'm just curious what fails first when a 3350 is pushed to higher rpm?
The smaller blowers couldn't take it for long. Overheat the bearings or pinions or whatever.
At race power, a plug suddenly misfiring from a bad coil could blow it up. Lots of stuff moving in one direction, does not like it when something slows down (like a back-fire). Too much mass moving to suddenly have some part get out of step with the rest. Kind of like a train, every car tightened up and pulling, then if one in the middle de-rails, it wrecks it all.
232 liked to blow a hole in the middle of the piston in #1 cylinder, as I recall. The master rod cylinder runs hot, probably due to being straight up (less oil).
As always, these comments are my personal opinions, not necessarily correct. Read at your own risk!!
And what always fails first is the financial backing of the racing program. This sport runs on cubic dollars.
The smaller blowers couldn't take it for long. Overheat the bearings or pinions or whatever.
At race power, a plug suddenly misfiring from a bad coil could blow it up. Lots of stuff moving in one direction, does not like it when something slows down (like a back-fire). Too much mass moving to suddenly have some part get out of step with the rest. Kind of like a train, every car tightened up and pulling, then if one in the middle de-rails, it wrecks it all.
232 liked to blow a hole in the middle of the piston in #1 cylinder, as I recall. The master rod cylinder runs hot, probably due to being straight up (less oil).
As always, these comments are my personal opinions, not necessarily correct. Read at your own risk!!
And what always fails first is the financial backing of the racing program. This sport runs on cubic dollars.
Yes, a bad coil will ruin your day, and your motor.
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