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pistoncan
01-23-2015, 02:23 AM
I was re-reading an article tonight comparing an engine similar to my corvair (which is supposed to be 100 net hp) to a O200 continental engine, and according to their testing, the O200's 100 hp is the gross horsepower, with a net horsepower somewhere in the range of 80-81 HP(based on actual thrust). Have any of you ever run across mention of these differences before? Are most aircraft engines rated at gross hp?

http://www.flycorvair.com/thrust.html

Just curious
Gary

Bruce
01-23-2015, 07:28 AM
O200 is 100HP at 2750. I would question their testing method. I looked at the corvair conversion and saw no reason for it when building my wagabond.

P.o.P.
01-23-2015, 09:12 AM
Not sure of "Gross" but Normally Aspirated engines are rated w/o an Exhaust System.

Turbo charged is rated with.

andya
01-23-2015, 11:51 AM
Not sure of the validity of info, but have also heard that the Gross HP does not include accessories such as hyd pumps, alternators.
Had also heard the exception in modern times is the I0-550 continental, it is rated at the 300 hp with all accessories running

pistoncan
01-23-2015, 03:08 PM
I think he was trying to measure the actual hp available to turn the prop. I have a feeling the engine will come out something under a 235. Not much power compared to most short wings. My overriding concern was cost.

Bruce
01-23-2015, 06:49 PM
O235 did power the clipper,pacer and colt. I paid 1700 for my complete O290G. It was zero time and the conversion was almost finished.