Io-390x

[TShort]

Anyone have any specifics regarding weight, etc of the IO-390 as it compares to the parallel and angle valve IO360's? I have found some stuff on the web but no specific comparisons.
I like the idea of the increased HP with low comp pistons, but don't know how much the weight difference is for the -8. I don't want a nose heavy airplane (and I'm light at 155lbs), and just finished the most recent RVator (keep it light) but the extra HP sounds cool!

Thomas
-8 flaps

[mahlon_r]

Generally speaking,the slant valve counterweighted 200 Hp IO-360 and the slant valve 210HP IO-390 should weigh about the same, as long as the accessories are configured the same. The non-counter weighted slant valve 200 HP IO-360 would be about 10lbs lighter then the counterweighted slant valve IO-390 and IO-360. The 180 HP parallel valve IO-360 engine with a forward facing sump and no counterweights would be about 22 lbs lighter then the counter weighted slant valve 390 and 360. Accessory configuration will vary these comparisons but generally speaking like accessory configuration and feature configuration should yield these results.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at you own risk."

[Captain_John]

Thomas,

Have you seen Dan's Weight and Balance data?

Lots of data here:

Dan's WAB page

It seems that the -8's are really sweet with the light 180's!

CJ

[Highflight]

Originally Posted by mahlon_r

Accessory configuration will vary these comparisons but generally speaking like accessory configuration and feature configuration should yield these results.
Good Luck,
Mahlon

Mahlon, so with the IO-390 w/EI, what kind of prop choices would we then have considering the limitations put on some?

[mahlon_r]

Vern, Better question for the prop guys as they assign the restrictions. In all practicality, I don't think it would be to much of an issue to run a prop, as if the engine were a 360 with EI. I think the vibration schedule wouldn?t be much different. So to me if the prop were OK with a 360 with EI it ought to be OK with the 390 with EI. Haven't done any testing but the small combustion chamber differences shouldn't make much of a difference.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at you own risk."