Chris Gentry wrote:

I did the internal grooving when I overhauled the engine but I am
considering putting an Air Blast Tube directed on the  plugs area since that
area has be determined to be a hot stress point..  Do you think this would
be worth while?
Regards, Chris Gentry
                Glasair Turbo Rotary
                 Dragonfly Turbo Subaru
                  Grumman Cheetah

Won't hurt Chris. Probably not worth it however as by the time
the heat gets out there the whole outside of the engine is near the same temp.
The new Power Sport had a gadget at OSH last year that bolted
aux water jackets around the spark plugs. I don't recall if they
instrumented the inner wall for temp like we are talking about here
so I am not sure that would work. Jim Mederer of RB uses an additional cold
water inlet to the front housing in line with the spark plugs
on his 900 HP turbo three rotor engines.

Paul Lamar
 
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