THROTTLE SETTINGS WITH AFP

N184JG · #1 01-22-2009, 09:10 AM

I would like to know about throttle settings with an AFP system.I have an ECI kit engine IO-360 with cold air induction ,high comp. pistons, LASAR ignition , AFP fuel injection and Catto prop.At full throttle 2000 msl 2700 rpm and 27.5 mp ,!/2 throttle 2700 rpm 27.2 mp ,1/4 open throttle 2610 rpm 25.2 mp at closed throttle 1200 rpm and on the ground 800 rpm. Anyone who is using AFP system what are you seeing?

N184JG · #2 01-22-2009, 05:28 PM

Am I the only one using AFP fuel injection?????

AlexPeterson · #3 01-22-2009, 06:28 PM

Quote:

Originally Posted by N184JG

Am I the only one using AFP fuel injection?????

No - but I don't think we understand your question or issue. It sounds to me like your MAP gauge is faulty, at the least. You didn't report MAP at idle. Or MAP on the ground with engine shut down.

I can't explain why rpm stays so high with a fixed pitch prop either.

A picture of your throttle arm showing the linkage would be helpful, also.

Is this problem on a brand new plane, or has something changed?

Need more info. please.

aerhed · #4 01-22-2009, 06:57 PM

That can't be real. Only way you could pull those numbers is if air valve (throttle) is actually moving at some exponential ratio. Map gage is out of whack or throttle cable slippin' or both.

aerhed · #5 01-22-2009, 06:58 PM

Did I say exponential? I meant logarithmic, I think. I hate math. I like wrenches.

mannanj · #6 01-22-2009, 07:07 PM

I would talk to Don at AFP. He is one of the most knowledgeable people on the planet on introducing fuel into the combustion chamber of an internal combustion engine. He advertises on this site.

N184JG · #7 01-22-2009, 07:41 PM

Been like this sense day one. I talked to Don at AFP he said that I had more air then needed everything was ok. I tried a second mp gauge it reads the same.I get full travel on butterfly from throttle to controler.I just would like to know what other people with AFP are seeing.

flion · #8 01-22-2009, 08:13 PM

Well, I don't think this will help a lot because my field elevation is 7000 and I often fly at 8500 to 9500, but my cruise MAP is usually about 20. If I climb higher, I see it start to drop and I think (still in test phase) that I hit full throttle 20" MAP about 11k to 12k. I fly my approaches at 10-13" MAP and it looks like the prop (at fine pitch) runs about 1100 to 1500 RPM. It's a constant speed, so the high settings are always the same. I haven't paid much attention to ground idle MAP but my EFIS log shows about 8" minimum; it's been cold so I've been warming up the engine and not staying at idle for very long.