Bubblehead

Bubblehead

Well Known Member
I cannot find the threads where this was discussed. Maybe someone can point me to them. The gist of it is the ramps in the upper cowl half at the inlet needs to be closed off at one end. Here are pictures of one of the ramps on my upper cowling.



The dark area in the left photo is an opening into the ramp and the right photo shows an even bigger opening at the outboard end of the ramp.

Which side do I close off, or does it even matter?

My engine and oil temps are fine but I have the cowl off while changing exhaust systems so I thought I would take care of this now too.
 
Extra work and weight

captn kirk said:
what would be the reason not to close both sides?
Click to expand...

All that you need to do is keep the air from moving inside the ramp from one side to the other. The amount of air that leaks through this will depend on how you made your baffle seal to cowl fit.

Kent
 
I did both sides

I did both sides after I had been flying the plane for some time. There are no temperature problems but there was little or no speed effect as I recall. Not worth digging back through my test data for.

Bob Axsom
 
Cooling Ramps

I did both sides of my 8, but was not happy with the way the middle baffle seal had to make such a contour to seal off properly. The problem was the baffle seal dropped off the side of the cooling ramp and left a place I felt would leak pretty bad. After many trial and error fits, I molded the middle section to contour better with the seals. A little styrofoam and glass and this is the result. The baffle seal lays in very tight and I believe will seal off much better than before. You have to be careful to leave clearance for the flywheel so it forms a well area at the front. I slicked it up nicely so not to cause undue turbulence and thinly painted it so cleanup would be easier.

http://picasaweb.google.com/decathlon737/RV8Cowl
 
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