View Single Post
Old 11-29-2015, 06:12 AM
Jesse's Avatar
Jesse Jesse is offline
Join Date: May 2005
Location: X35 - Ocala, FL
Posts: 3,711

Originally Posted by newt View Post
That's on your IO engine. If you had mounted the EGT sensors a quarter-inch further down the pipe, you'd be expecting EGTs in the low 1100's for takeoff and initial climb.

Absolute values don't matter, only matters whether they're increasing or decreasing as you lean out.
That's not just on my IO. I have flown at least 20 different RV's with IO's and they are the same. Low 1200's on takeoff, peak at around 1450 when at or below 65% power. 1400 on takeoff, plainly said, is too high, no matter where the probe is. Absolute number don't tell the whole story of what is going on, but they do mean something. By your argument EGT's at 1800 wouldn't matter. 1/4" further down the pipes won't change over 100 degrees.

A variation of 100 degrees among EGT's doesn't tell much, but a difference of 300 degrees does, assuming same sensors and roughly the same position in the exhaust.

1400 on takeoff is too high. It's running too lean, causing high CHT's.
Jesse Saint
Reply With Quote