Just a comment on one of the "assumptions" we all start with when

discussing estimation of cooling system sizes for hot weather:  How much hp

is being developed, i.e., how much heat is to be rejected?

   - I wonder if everyone is "assuming" that they must calculate radiator

areas based on heat being generated/to be rejected while generating 100%

power, i.e., 160 or up to 180-205 for a n/a rotary, depending on what you

think you will be getting?

        --  My point is this:  At a 90 or 100 degree F day, at full

throttle, sea level, std day pressure (29.92), you won't be generating 100%

power - because, you are sucking in hot ambient air through the induction

system (lower density than standard) and, without looking up the equations

for normalizing measured performance to "std day", I guess we'll be

generating only 90% of the 160 or so hp.

 

That’s true.  That is one of the considerations built into my assumption of designing to 80% of full power on a hot day.  The other thing is, it would probably very fortuitous if your actual performance fell within +-10%, or even +-20% of your design point anyway.

 

Al