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  #11  
Old 12-15-2017, 05:45 PM
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DanH DanH is offline
 
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Quote:
That's good advice re the cooling baffles etc. especially the over-rich mixture for excessive cylinder wear.
As we all know a 360 produces around 160HP at T/off with a FP prop so the FF sounds about right.
160 is maybe a little low for 2600 RPM. Obtain an accurate HP for the average installation from a Lycoming power chart, then do some simple math.

Call it 170 HP at 2600, and use 0.55 BSFC, roughly 125F ROP:

(170 HP x 0.55 BSFC) / 6 lbsgal = 15.6 GPH initial flow.
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  #12  
Old 12-15-2017, 11:43 PM
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Quote:
Originally Posted by DanH View Post
160 is maybe a little low for 2600 RPM. Obtain an accurate HP for the average installation from a Lycoming power chart, then do some simple math.

Call it 170 HP at 2600, and use 0.55 BSFC, roughly 125F ROP:

(170 HP x 0.55 BSFC) / 6 lbsgal = 15.6 GPH initial flow.
I just checked the data from my previous post (#4) -


15.5 gpm at 2400 rpm and 5,500 ft DA runway.

Sensenich FP prop O-360-A1A with carb.


Dynon was reporting about 80% power at 100 kts IAS - This is around 144 HP

I think your 2600 rpm for a Fixed Pitch climb may be too high. Later in the flight a lean to peak check probably put the take off at around 150 F ROP , giving a BSFC of around 0.65.

I think your 170 HP assumption may be off.

A big thank you to savvyanalysis.com and Dynon for all of the data collection and display.
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Last edited by az_gila : 12-15-2017 at 11:46 PM.
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  #13  
Old 12-18-2017, 09:34 PM
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I've not seen 2600 in the climb with a FP prop unless of course it's bent fir climb perf only. Older engines down on comp often see 2300 at best. It's all a trade off with FP.
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  #14  
Old 12-31-2017, 11:05 AM
andreskatz andreskatz is offline
 
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thanks to all responders
i have not installed the wheel pants or fairings which is next in line
my prop is a fp sensenich and i see 2600 on climb i figure i have a climb prop but temps limits my time going up
my buddy in his rv7 can outclimb me but then once level i have to pull back 2-3 inches so he can keep up with me, he has a CS prop
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  #15  
Old 12-31-2017, 11:40 AM
gasman gasman is offline
 
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Quote:
Originally Posted by andreskatz View Post
thanks to all responders
i have not installed the wheel pants or fairings which is next in line
my prop is fp.
my buddy in his rv7 can outclimb me but then once level i have to pull back 2-3 inches so he can keep up with me, he has a CS prop
Very impressive without fairings..........
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  #16  
Old 12-31-2017, 12:13 PM
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skylor skylor is offline
 
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Quote:
Originally Posted by andreskatz View Post
thanks to all responders
i have not installed the wheel pants or fairings which is next in line
my prop is a fp sensenich and i see 2600 on climb i figure i have a climb prop but temps limits my time going up
my buddy in his rv7 can outclimb me but then once level i have to pull back 2-3 inches so he can keep up with me, he has a CS prop
If youíre seeing 2600 in climb, what RPM are you seeing level? Isnít the Sensenich limited to 2600 max?
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  #17  
Old 12-31-2017, 12:23 PM
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az_gila az_gila is offline
 
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Quote:
Originally Posted by skylor View Post
If you’re seeing 2600 in climb, what RPM are you seeing level? Isn’t the Sensenich limited to 2600 max?
Not the 180HP O-360 prop.
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  #18  
Old 01-01-2018, 10:33 AM
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What are the egt when you are seeing high cht? That is important to determine if it's decent fuel mixture or if you are lean. 1100 or 1200 egt is normally recommended in full throttle take off. The most you would want to see is 125-150 rich of peak which is around max power mixture. Any leaner than that and you are losing performance and will have higher cht.

If egt are in the correct range then as suggested I would look into correcting the baffling. I had a heck of a time with baffling on my t18 but after a few flights and changes I dropped 75* off my cht.

Maybe I missed it but what cht are you seeing? Seems like everyone has their own version of "too high". Our local ap said "keep it under lycoming max and it's fine " but others seem to freak out when I say mine rise to 400 in long climb and sit at 360 for cruise. Both well within normal operating range per lycoming and far below the 525 max for an o290.
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  #19  
Old 01-01-2018, 01:47 PM
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N941WR N941WR is offline
 
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Before you rip into your carb, have you checked your timing?

If you have even a degree or two too much advance, you can see high CHT's.
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