lml@lancaironline.net Mailing List Archive

<<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> Tom & Group: While preparing to test fly the IV over in Dubai last year I was quite concerned about heat with the standard cowl outlets and could not convince Amin to increase the size to the DP's. Much to my surprise he cut the exhaust ramps on the inside, about mid height and pushed the remaining lower edge down about 1 1/2"-2". Then he glassed over the resulting wedge opening and it looked great. Result was that in 120-140 deg. temps, doing pattern work, slow flight etc the engine never overheated... On the flip side, the DP's have created a reverse problem in that the engines never reach optimum temperature. This last winter I had to stop flying a new IV in Chicago because we could not get the CHT's over 300 deg. in cruise. Last month I re-flew the airplane and the temps were barely in the normal range, and I had to close the oil cooler door to get the O/T to the desired 200 deg. It would hang around 180 where the thermostat is set at...... Remember that in order to achieve optimum clearance on all those moving parts the engine must be at normal operating temp, and all parts expanded to normal size. Engine temps that are too cold are in my opinion just as bad as too hot... Why do you suppose TCM in their wisdom require 100 deg. oil temp before run-up or flight ?? WEAR-oh-WEAR has my engine gone !!!! Mike DeHate (the original) >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML website: http://www.olsusa.com/mkaye/maillist.html LML Builders' Bookstore: http://www.buildersbooks.com/lancair Please send your photos and drawings to marvkaye@olsusa.com. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>