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Bevan

Well Known Member
OK, So last night I searched the archives and the internet for hours and hours. I could not find what I was looking for before my eyes went square.

Does anyone have a % power chart for the Lyc 0-360-A series with enough entries for the RV altitudes (up to 18,000) to saticefy GRT's EFIS table that you feel confident are pretty accurate?

I assume this chart should use ROP figures as that's most important to know before leaning. I can easily enough calculate LOP % power via fuel flow once leaned.

Thanks

Bevan
 
You should be able to get the values you need from this spreadsheet which replicates the official Lycoming power chart for the O360-A series engines. It gives results that are extremely close to the Lycoming spaghetti diagram (i.e. the power chart).

You'll need to iterate to find the MP values needed to produce the target power at each rpm and altitude, so it will take a bit of work.
 
Actually, there is a simpler way (simpler for you, not for me).

I have a Python program that does the same calculations as the spreadsheet. If you tell me which altitudes, rpms and powers you want, I could very quickly write a short Python script that would crank out a table of altitude, power, rpm and MP. If you explain what order and format you want things in, to make your data entry easier, I could make it look pretty much any way you want.
 
Kevin. Looks like the GRT chart that Tim pointed out has all the info I need. I will assume for the moment that it is accurate. Thnaks for your offer.

Tim, Thanks for the link to GRT. I scowered the manual but didn't think to check their website.

My engine is slightly different in that it is now fuel injected with Pmags so the actual max power may be higher causing the % power to read slightly lower. But its a good starting point. I assume I will only be using this feature to know when I can begin leaning.

Once leaned, I will use the following formula to determine % power.

% power = 14.9 X FF (gph) X 100/180HP

Bevan
 
Close enough

I have the same setup, dual EI, fuel injection. But personally, I don't think these make more than maybe 5% difference from mags and carb. Just an educated opinion from comparing different Lyc models, you don't see any significant increase until you move to angle valves cylinders or higher C/R pistons.
Tim
 
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