Superior recommendations concerning leaning

[MrNomad]

I now have 45 hours on my Superior A1A1 carbed O-360 engine in my 9A. Performance and reliability has been excellent. I asked Superior for their official recommendations concerning leaning. Pls read their comments.

Barry
Tucson

Hello Barry,

Glad that you are enjoying your new engine!

Here's the official Superior recommendations with regards to leaning:

At 100% power stay full rich at sea level and for higher altitudes lean until the engine just smoothes out. This will put you somewhere between 100 degrees and 200 degrees Rich of peak EGT. You will need to experiment a bit with your engine to find the exact point on your EGT gauge. You need that extra fuel to keep cylinder head temperatures down at higher power settings for a long engine life, fuel is cheaper than cylinders.

At 75% cruise power setting you can safely run anywhere from 25 degrees lean of peak to 50 degrees rich of peak. If the longest possible engine life is your goal, stay on the rich side of peak.

At 65% and below you can run pretty much lean as you like without fear of damage to the engine. Leaning beyond peak EGT at lower power settings will actually drop cylinder head temperature with a nice drop in specific fuel consumption to go along with it.

Use of AutoGAS will not change leaning recommendations but can effect sensitivity of the EGT instrument as you lean.

Hope this helps,

John Weber
Superior Customer Support

[Jerry Cochran]

Thanks,

Good info from them. With my XPIO-360 , I've had zero problems in my -6a
I usually go a bit lean of peak for cruise at 23x2300. This results in a fuel burn of 8.3gph +/-. Mine runs cool, CHT's around 350f. Oil temps too low, need an outlet flap on cooler. Cruise climb 24x24 I will lean to 1350 EGT, safely on rich side, CHT's still cool.

Jerry

[asav8tor]

Originally Posted by MrNomad

fuel is cheaper than cylinders.

Lets say you are a very aggressive leaner. Then compare to another pilot that flies around very rich you average a 2gph lower fuel burn. Over the course of 1,000 hours you trash your cylinders an need to replace them because you over did it.

Gas $5/gal x 2000 gal = $ 10,000

New cylinders $1000 per x 4 = $ 4,000

[Yukon]

Originally Posted by asav8tor

Lets say you are a very aggressive leaner. Then compare to another pilot that flies around very rich you average a 2gph lower fuel burn. Over the course of 1,000 hours you trash your cylinders an need to replace them because you over did it.

Gas $5/gal x 2000 gal = $ 10,000

New cylinders $1000 per x 4 = $ 4,000

Drop an exhaust valve on takeoff............PRICELESS!

[frankh]

Originally Posted by asav8tor

Lets say you are a very aggressive leaner. Then compare to another pilot that flies around very rich you average a 2gph lower fuel burn. Over the course of 1,000 hours you trash your cylinders an need to replace them because you over did it.

Gas $5/gal x 2000 gal = $ 10,000

New cylinders $1000 per x 4 = $ 4,000

At 65% or lower (if that is indeed the magic LOP point)running LOP should actually increase cylinder life for two reasons.

1) They will run cooler (mine run at 300 to 320F)
2) The wasted fuel (and it is wasted) running ROP is also removing oil from the cylinders..theu less lubrication =more wear.

Can I prove point #2?..No but I bet the difference will be such that saving the fuel will be way more cost effective...And the cylinders should go to TBO or beyond.

Frank

[frankh]

Originally Posted by Yukon

Drop an exhaust valve on takeoff............PRICELESS!

Thats just scare mongering and has no basis in real life.

nobody is going to drop any exhaust valves because that have been running LOP for 2000 hours.

At least I hope not..

Frank

[osxuser]

Talk to Tornado Alley Turbo (GAMI owned?), they have a LOT of experience with LOP as it's their SOP for their turbo normilizer kits. Hundreds of Cardinal RG pilots and Bonanza drivers run LOP too. I've seen no ill effects of such operations, and I lean the **** out of whatever I can, temps allowed.

[Captain_John]

Originally Posted by Yukon

Dropping an exhaust valve on takeoff............PRICELESS!

OMG!

That was one of the funniest comments I have read here in quite a while!!!

My two...

If carb'ed... stay 50 rich!

CJ

[Walt]

Carbed and 50 lean all the time 55-65% pwr, 7-8 gph.

[Walt]

Carbed and 50 lean all the time 55-65% pwr, 7-8 gph.