Saito 82 test flights after being balanced

Test flew the Tony with the Saito 82 today. Vibrations is now less than the 72 Saito. Power was up also. The prop 13.25 by 4.2 3 blade Brian Eather which I used at Muncie gave me 5.2 lap times is now giving me 4.6 lap times. Lots of power. So I`m going to a smaller venturi to slow it down.Because of less vibrations it`s putting out more power.Cool.Now to get the lap times back to 5.2. Just thought some of you would like to know the out come that have tried the 82.
Balancing works for it.

Gordy

So, don't leave us hanging--how exactly did you balance it? (I apologize in advance if it is mentioned elsewhere).

>Test flew the Tony with the Saito 82 today. Vibrations is
>now less than the 72 Saito. Power was up also. The prop
>13.25 by 4.2 3 blade Brian Eather which I used at Muncie
>gave me 5.2 lap times is now giving me 4.6 lap times. Lots
>of power. So I`m going to a smaller venturi to slow it
>down.Because of less vibrations it`s putting out more
>power.Cool.Now to get the lap times back to 5.2. Just
>thought some of you would like to know the out come that
>have tried the 82.
>Balancing works for it.
>
>Gordy

I knew it.

Gordo.....
Am I missing something here? You are squeezing an .82 down and reducing the horsepower.....why use a bigger motor in the first place, if that's the deal?
Don't 4 strokes respond to flattening the prop?

Pretty plane...glad it's airborne again!

See Ya

LAST EDITED ON Oct-05-04 AT 09:41 AM (CDT)
 
Answers to some of the questions brought up here.Greg Settle in Colorado Balanced the engine for me. He lighten the piston and wrist pin.Then removed some weight off the crank at the connecting rod end.Then added some tungston metal to the counterbalance end. The crank was under balanced. And to the other question is yes the four strokes do respond to less pitch,I`m already down to 4.2.So it is easier to change the venturi than repitch all my props.Even with the smaller venturi it puts out more power than the 72. If I loose the power then I`ll repitch the props.Hope this answers your questions OK/

Gordy

One thing I forgot to mention was after the repairs I rubbed the Tony out. Which also made the lap times quicker.Darn I wish I had`nt done that. But it look good though.

>(snip) One thing I forgot to mention was after the repairs
>I rubbed the Tony out. Which also made the lap times quicker.
>Darn I wish I had`nt done that. But it look good though.

At the speeds at which we fly and with the available thrust at hand I wouldn't have thought that would make much noticeable difference. Are you sure there wasn't something else involved (weather changes, maybe?) Or did you have a sandpaper finish on it before it was rubbed out?

Leonard,
It had a nice finish but never rubbed out. My Colossus was test flown before it was rubbed and when I rubbed it out I had to change the pitch a .25 of pitch to get it back to the right lap times. The Tony is bigger and it has a lot of drag with the oil cooler hanging down. It now also glides longer than it did before.

Gordy

Gordon-

Someone may have to correct me here, if I've missed something. However, it seems to me that since Power = Thrust x Speed (P = TV), and speed and thrust would have to remain constant for retention of original lap times with the same plane, you would have to reduce the power to that of your original engine to increase lap times to their former value. Perhaps the venturi would improve fuel draw, but you'd be sacrificing some great performance improvement in verticals and in maintaining speed in tight turns. If your plane really has less drag now, it appears that you would even have to reduce your engine performance more to return to your original lap times. Climb should really be improved with a decrease in prop pitch. Perhaps you could do both and enjoy both increased power and draw. Increased diameter could also be a solution that would aid some aspects of performance, if it did not hinder pitching authority. Just my thoughts.

SK

Serge,

This is the same engine I was running at Muncie.I used the 13 by 4.2 Brian Eather three blade. The 82 was turning it at 10400rpms. It had lots of thrust for the verticals and over heads.I think I`d be turning it at 11,000rpms by going down in pitch? I don`t think the pipe ships launch at that rpm,maybe 9,800 to 10,200.I`ll let you know how it goes. I`m going flying tomorrow.

Gordy

>Gordon-
>
>Someone may have to correct me here, if I've missed
>something. However, it seems to me that since Power = Thrust
>x Speed (P = TV), and speed and thrust would have to remain
>constant for retention of original lap times with the same
>plane, you would have to reduce the power to that of your
>original engine to increase lap times to their former value.
>

It is supposed to work that way, but it never does. There are many mysteries to speed and power.

This is just incredible! It appears that the "rework" for the Saito's is rebalancing. Please ask Greg about the Saito 91 for me. Or, if he has an email address, I would sincerely like to know it.

Milton,

Greg Settle does not have an e-mail but, His phone no. is (303) 343-8778. I`m sure you could call him and talk to him. He does alot of engine work for speed fliers. He does good work also.Lives in Aurora Colorado.Hope this helps.

Gordy