VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

  #1  
Old 10-10-2017, 06:16 PM
macrafic's Avatar
macrafic macrafic is offline
 
Join Date: May 2006
Location: Rochester, MN
Posts: 370
Default ICO RPMs

First flight with an RV-7A, 3-blade Catto fixed pitch prop and IO-360-M engine with dual pMags. Getting 730 RPM ICO on the ground and 810 RPM ICO in the air (on landing). Seems a bit high to me, but I am not really that knowledgeable.

Can those of you with a similar setup share your ICO RPMs with me? Am I in the ballpark? High?
__________________
Rich and Cindy Macrafic
Rochester, MN
One month to painting and test flying
Reply With Quote
  #2  
Old 10-11-2017, 03:49 PM
penguin penguin is offline
 
Join Date: Jan 2005
Location: England
Posts: 1,015
Default

Are you mixing up terms? ICO usually means Idle Cut Off and refers to the mixture control pulled fully out.

Do you mean with the throttle closed?

First of all, if you have a new engine the idle speed will change over the first few hours. 650rpm might be desirable at idle, but with a light weight wood prop you may have to accept a slightly higher idle to keep the engine running at all smoothly. Idle when you are just about to land is a factor of the prop and your ground idle speed. Perhaps stick with what you have for the first few hours, always assuming you have a long enough runway to operate from.

Pete
Reply With Quote
  #3  
Old 10-11-2017, 03:59 PM
Raymo's Avatar
Raymo Raymo is offline
 
Join Date: Nov 2014
Location: Richmond Hill, GA (KLHW)
Posts: 1,386
Default

RV-7A, Catto 3 blade with 20 lb crush plate, single P-Mag and one Slick with AFP FI. I see about the same numbers; maybe slightly higher at idle with mixture just rich enough to keep the engine running when taxiing.
__________________
Ray
RV-7A - Slider - N495KL - First flt 27 Jan 17
O-360-A4M w/ Catto 3 blade NLE, AFP FM-150 FI, 1 PMag, Vetterman Trombone Exh, SkyTech starter,
PlanePower Alt, FlightLines Interior, James cowl & plenum
All lines by TSFlightLines
NSDQ

"The object of the game, gentlemen, is not to cheat death: the object is not to let him play."
Patrick Poteen, Sgt. U.S. Army
Reply With Quote
  #4  
Old 10-12-2017, 08:23 AM
Robert Anglin Robert Anglin is offline
 
Join Date: Mar 2008
Location: houston, texas
Posts: 719
Default Your fine.

As has been said above a light wood prop does need a little more RPM at idle set to be smooth and stay running better. A nice heavy metal prop is kind of like a fly-wheel and can stay smooth with more mass at a lower idle set point.
We run a light 12-13 pound Prince and set our ideal at around 820-850 RPM's.
I even run it a little above that on the ramp to keep the plugs cleaner a little longer. I think you are OK here with this, but it is you that have to be comfortable with you settings. Hope this helps, Yours, R.E.A. III # 80888
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 10:06 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.