Fred,

 

One doesn't have to pay for the "horsepower" gains from ram air, but I agree with everything else, except your question. 

 

Yes, if I were building today, the bottom of my cowl and airframe would look a lot different. Cooling drag reduction thru augmentation with a benefit from a wee bit of thrust to boot, ahhhh.  Not to mention the ear splitting addition of the noise to scare those on the ground and in the air.

 

I knew nothing when I started building last century - Now I know just enough to get myself into trouble. 

 

No, I am through experimenting with my flying lawn dart and its beautiful cosmetics.  Augmentation would require exhaust pipe and cowl modifications at the very least.  Then I would entrap myself with a cold induction system.  Arrrrggghh, it never ends.

 

We are all waiting for your computation-justifying flights. Alas, you are not done just yet.

 

Scott

 

“There is a free lunch - or at least a cheap one.”

Right you are, Scotty!  I merely was pointing out that one has to pay for more horsepower, or work for drag reductions.

However…..

There may be another nearly free lunch.  Exhaust thrust. 

I have a WWII NACA tech paper discussing the theoretical and experimental work done to determine the potential thrust from the exhaust of aspirated piston engines.  The faster you go, the more effective it can be.  So after evaluating all the cooling drag reduction work I have done, I plan to work on this area next.

First I will have to wade through all the equations and data and attempt to understand and interpret it with my ever-shrinking neuronal capacity. That is a project for the latter half of the year. Trading more back pressure (and presumably some power loss) for thrust improvement (via exhaust nozzles) is an interesting trade-off.

  It is not a simple one.

“Combining power gains with drag reductions [and perhaps some augmentation of exhaust thrust] results in significantly greater performance.”

Want to try some experiments?