Here is another way to think about the difference. A 360 is 1.125
times the displacement of a 320. If the optimal fuel/air ratios are the
same for an equal rpm, the 360 should require 12.5% more fuel. Then again,
180 HP (360) is 12.5% more than 160 HP (320) - Of course that is a maximum power
comparison at sea level.
Fuel sipping (running LOP, power < 75%) requires that the little
individual engines (cylinders) are delivering the same HP in order to avoid
mayhem and vibration from unequal combustion events. That means managing
(equalizing) the F/A for each cylinder at the desired power level. A
measure of this is to perform the GAMI lean test (
http://www.gami.com/gamilean.html ).
Resolving imbalances is a whole other story.
Grayhawk
In a message dated 7/7/2008 7:39:42 A.M. Central Daylight Time,
rsmiley2@centurytel.net writes:
I opted for the 360 for several
reasons.
1. greater performance for addtional safety
margin on short runways, high densitity altitude conditions, and load
performance. Also it is my understanding that if you want fuel economy,
pull the throttle back and sip your fuel. The economy should be
similar to that of the 320. It would be more advantatageous to have the
360