Van's Air Force
Don't miss anything! Register now for full access to the definitive RV support community.
Fuel Burn with the 390?
- Thread starter kdedmunds
- Start date
N941WR
Legacy Member
9.1 GPH at 65% power.
I couldn't find the 75% burn on Lycoming's site but did find one site that listed 12.5 GPH for the 200 HP IO-390.
I couldn't find the 75% burn on Lycoming's site but did find one site that listed 12.5 GPH for the 200 HP IO-390.
Last edited:
There are a lot of variables.
Saw your request earlier, so I got a photo this afternoon on the way back from Mobile. It's what might be fairly described as an average "economy" setting at an average (?) altitude. Mixture is set at peak EGT, so it's not actually making 65% power; the EFIS is considering only MP and RPM. The resulting 8.8 GPH is misleading...too low. A Best Power mixture (say, 125 ROP) with the same MP/RPM would be more like 10.5 to 11.
The 9.1 GPH figure from the Lycoming webpage is too low for best power mixture at 65%. It doesn't even match the published Minimum Fuel Flow chart from the operating manual. At minimum flow, 9.1 would be 60%:
Saw your request earlier, so I got a photo this afternoon on the way back from Mobile. It's what might be fairly described as an average "economy" setting at an average (?) altitude. Mixture is set at peak EGT, so it's not actually making 65% power; the EFIS is considering only MP and RPM. The resulting 8.8 GPH is misleading...too low. A Best Power mixture (say, 125 ROP) with the same MP/RPM would be more like 10.5 to 11.
The 9.1 GPH figure from the Lycoming webpage is too low for best power mixture at 65%. It doesn't even match the published Minimum Fuel Flow chart from the operating manual. At minimum flow, 9.1 would be 60%:
Last edited:
HeliCooper
Well Known Member
