Bill, I will try flying it without the cowling the very next hot day we get here... looks like next Thursday. Thanks for the reminder. I did fly it 6 weeks ago without the cowl and found it very good and was thinking at the time that even an engine low on water would still fly cool in this situation, but as I remember, that day was not a warm day. It will be very interesting to do it again in hotter conditions. BTW... I found the elevator not very responsive and also with a light shudder at low speed...but | suppose thats normal without the cowl.
There were no tell tale signs of carbon according to your last post, so thats a relief, but I think I will do that checks you speak of asap anyway, because it might show some marks that might explain why I lost the rpm on WOT. I tried a while ago but broke my allen key trying to get a bolt out. I will buy a better quality set and try again.
Thanks for the tip Bill. And I hope it does become "Aachem's razor" haha... at least then I will know everything else is ok. I have my doubts though somehow because I never noticed any over heating last summer. Maybe I wasnt noticing because of other problems I had at the time.
Oh BTW..... Those measurements in the pic of the last post were in metric... translated = 9" x 6".
Mike