lml@lancaironline.net Mailing List Archive

<<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> Posted for "Larry Klaas" <ldk1@firstworld.net>: Maybe I am missing something, but seems to me absolute temps are more important a consideration than how far ROP or LOP an engine is operated. I would like a clarification from some engine gurus out there in Lancair cyberspace. If engine components can withstand certain temps before failing then what difference does it make how for ROP or LOP the engine operates? I run my 4-P based on absolute TIT temps, CHT temps, EGT temps. Why care if it is operated at peak as long as the component temps are within limits? I have read all the GAMI website stuff and it makes sense. When I run on the lean side I get a slight roughness, and since I don't like roughness at all, I don't run there. I have flown in some 4-P's that do not run rough on the lean side. I do know that CHT's are lower on the lean side, and in my plane I cannot run at higher power settings ROP in the flight levels without overheating. I run about 28" and 2300 (59%) up high and temps are OK. I like to keep CHT's under 400 and TIT's under 1650. The engine operating manual from TCM says CHT under 420 continuous and TIT under 1750 continuous. Dale Sholtz has a 4-P he runs on the lean side back and forth to Mexico from Montana, and he runs at 31" and 2300 RPM with CHT's about 365 and TIT's in the 1550 range. He has in 5 years operation about 700 hours and it is running fine. He mentioned to me that his ran slightly rough at first on the lean side until he tweaked his plugs and mags, then it smoothed out. I don't know about the detonation issue however. Any comments from you engine experts on the above would be appreciated. Larry Klaas Klaas Development, Inc. 9333 E University, Mesa, AZ 85207 Tel: 480-354-7138 Fax: 208-361-5849 Email: LDK1@firstworld.net N51LK LML website: http://www.olsusa.com/Users/Mkaye/maillist.html LML Builders' Bookstore: http://www.buildersbooks.com/lancair Please send your photos and drawings to marvkaye@olsusa.com.