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Lycoming I/O360 idle RPM?

Aquaman!

Member
I have recently purchased a Dick Colliander built RV-8
It has been over 3 years since my RV-8 has flown and I recently swapped a slick mag with an Emag electronic ign, installed an EchoUAT ADS-B. Before I reinstall the nose bowl for test flight I'd like to reset the idle rpm. Any suggestions for minimum idle RPM?
Also,
I'm putting together a POH for my recently purchased RV-8. Does anyone know a good source for an operators manual and possibly a Pocket checklist (PCL) that fits in the glove box?
 
I have recently purchased a Dick Colliander built RV-8
It has been over 3 years since my RV-8 has flown and I recently swapped a slick mag with an Emag electronic ign, installed an EchoUAT ADS-B. Before I reinstall the nose bowl for test flight I'd like to reset the idle rpm. Any suggestions for minimum idle RPM?
Also,
I'm putting together a POH for my recently purchased RV-8. Does anyone know a good source for an operators manual and possibly a Pocket checklist (PCL) that fits in the glove box?

You should check out Kevin Hortons website. He is a test pilot and did an excellent job of his POH - - Not likely a pocket size though. :D
 
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My angle-valve IO-360 has idle set at about 600. With the very light WW prop, it is a little bit lopey, but OK.
 
A well tuned Superior IO-360 angle valve engine can idle below 250 RPM's.
I have one with a AFP-200 and two Aerosparks electronic ignitions that does just that. Smooth as silk. Timing is very important at that low RPM. Must be no more than 0 advance BTDC.
 
A well tuned Superior IO-360 angle valve engine can idle below 250 RPM's.
I have one with a AFP-200 and two Aerosparks electronic ignitions that does just that. Smooth as silk. Timing is very important at that low RPM. Must be no more than 0 advance BTDC.

I didn’t know it was possible to set the idle this low.
Is there any hesitation if you rapidly advance the throttle?
 
With an AFP-200 throttle body. I can advance the throttle normally. If I advance it too fast, it gets too lean to run and dies. Maybe with electronic fuel injection it could work.
 
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I will check the pressure next time I run the engine. It's at 50lbs. at 1000 RPM's, 75lbs. at 2500 RPM's all @ 180F. I only idle 250 RPM's on shut down.
 
Do you have an CS of FP prop? On the 10, I set RPM for what is smooth. However, my 6 has an FP and I set it 100 or so lower than optimal. This helps me to slow down a bit on final approach. Down side is, once on the the ground and hot, I need to bump the throttle a bit to keep it going.
 
I’m curious. What do you see for oil pressure when the pump is turning that slow?

And what about the voltage from the alternator when running that slow? My IO540 PP alternator sets off alarms when I try to idle below 750.

-Marc
 
OK. Oil temp 180f. RPM 420 alternator too slow to charge battery. Oil pressure 35 lbs.

RPM 235. Oil pressure 25 lbs. Engine still running smooth.
 

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Curious as to what might cause a change in idle operation. I had a recent experience where I was trying to make a taxiway and so I pulled the throttle completely once I made the runway and left the throttle at idle. I made the taxiway but the prop stopped. Never had that happen before. Treating it like a hot start I got the plane started again. Testing now shows that I cannot idle except at the first run up of the day. Engine is an IO 360. Idle setting seems to be 500ish. More testing before I decide to up idle to 700.
 
I'm still in build mode, so not RV specific, but all of the IO360 C172s that I fly have the idle set around 600ish. This includes planes with one E-mag.

However, the electrical system isn't happy unless you bump it up around 700 or so with the throttle.
 
With an AFP-200 throttle body. I can advance the throttle normally. If I advance it too fast, it gets too lean to run and dies. Maybe with electronic fuel injection it could work.

So how does that relate when on approach you are pulled right back to idle & you suddenly need to apply power? Like a missed approach, or such.
 
The rpm would never be that low (250) during an approach.

No, I agree, but throttle butterfly would be virtually closed and with windmilling rpm will create extremely low MAP guaranteeing a burp in engine power when throttle advanced, more so with quick advance, hopefully not dying.
 
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