Matched engine speed
01-22-2003 | 12:25 AM
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From: Enfield,
NC
Matched engine speed
First Twin, C-160, OS46 2 strokes. How close in RPM do engines need to run, and do you turn INTO or AWAY FROM engine out? Thanks, WLJ
01-22-2003 | 04:09 AM
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From: Saint Peters,
MO
Engine RPM
I try to get the engines on my Duelist (OS 46's) within 300-400 RPM of each other at about 2/3 throttle. Even a 500 rpm difference is barely noticeable in the air. I have flown it with as much as a 1000 rpm difference, which definitely made the plane pull to one side, but a little rudder trim took care of it.
Once I accidentally flew it with a 10-8 prop on one engine and a 10-7 on the other. I was amazed at how noticeable that was! Even though I'd sync'd the engines pretty good the plane really wanted to turn on me once airborne.
I got hung up on trying to sync my engines when I first got the plane (even bought a tach that I now barely use) but soon realized that it's more important to get them running good and reliably (usually on the rich side). I then just stand in front of the plane and listen to the sound as I run the engines up - if you get a "warbling" sound instead of a constant "drone" they're too far out out of sync and need adjusting.
Good luck with your twin!
Jim
Once I accidentally flew it with a 10-8 prop on one engine and a 10-7 on the other. I was amazed at how noticeable that was! Even though I'd sync'd the engines pretty good the plane really wanted to turn on me once airborne.
I got hung up on trying to sync my engines when I first got the plane (even bought a tach that I now barely use) but soon realized that it's more important to get them running good and reliably (usually on the rich side). I then just stand in front of the plane and listen to the sound as I run the engines up - if you get a "warbling" sound instead of a constant "drone" they're too far out out of sync and need adjusting.
Good luck with your twin!
Jim
01-23-2003 | 02:44 PM
#6
Matched engine speed
Before matching engines, don't forget to match props!! Otherwise, matching engine RPMs is meaningless.
Take a few props (of the same size, Jim
), and run them on the same engine at full throttle. Match the props in pairs that have the closest RPMs.
- George
Take a few props (of the same size, Jim
), and run them on the same engine at full throttle. Match the props in pairs that have the closest RPMs.- George
01-23-2003 | 11:06 PM
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From: Collierville,
TN
Matched engine speed
Originally posted by mulligan
Before matching engines, don't forget to match props!! Otherwise, matching engine RPMs is meaningless.
Take a few props (of the same size, Jim), and run them on the same engine at full throttle. Match the props in pairs that have the closest RPMs.
Before matching engines, don't forget to match props!! Otherwise, matching engine RPMs is meaningless.
Take a few props (of the same size, Jim
), and run them on the same engine at full throttle. Match the props in pairs that have the closest RPMs.
01-23-2003 | 11:49 PM
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From: Collierville,
TN
Matched engine speed
Originally posted by mulligan
Seems, ahem, provocative.
Seems, ahem, provocative.
There's a group of us that have learned how to tame them and make reliable runners out of them. I just call it "Cox-a-holics Anonymous" and whimsically made up the logo and use it as my avatar. I guess those with a perverted side might read something else into it but hey, check the spelling!
