Paul Johnson
Member
I have a cylinder head temperature situation on my RV-7A that I don’t understand, and I’m hoping someone can enlighten me. Cylinders #1 and #2 are running about 30 deg F hotter than #3 and #4. I have searched through VAF and have not seen this issue discussed. We are still in phase one test, with about 15 hours on the engine. The engine is an Aerosport O-360-A1A with ECI Titan cylinders turning a Hartzell BA prop. Mag on the left, Lightspeed Plasma II on the right. We have sealed every air leak we can find. We tried cutting down the dams on the front cylinder heads, which made the rear cylinders run cooler, but didn’t do a thing for #1 and #2. We installed Van’s lower cowl louver kit which lowered all CHTs significantly, but we’re still seeing about 400 degrees on the front cylinders and about 370 degrees on the rears in steady-state cruise at 75% power. We have not put the wheel pants on yet, so cruise speed is about 125kts.
From what I have read, these temperatures are acceptable for a new engine, but I sure don’t understand why there is such a discrepancy between the front and rear pairs of cylinders, with #1 and #2 running hotter. It doesn’t seem intuitive. Is it a problem?
Thanks in advance.
From what I have read, these temperatures are acceptable for a new engine, but I sure don’t understand why there is such a discrepancy between the front and rear pairs of cylinders, with #1 and #2 running hotter. It doesn’t seem intuitive. Is it a problem?
Thanks in advance.