On May 31, 8:27 pm, "Kyle Boatright" wrote:
I do not have first hand experience, and there are probably very few people
who have a lot of first hand experience flying in your relatively high
altitude environment. However, quite a few of the folks in the RV community
who elected to go with high compression pistons in their engines will tell
you that they wouldn't do it again. Some report a rougher running engine,
most report a hotter running engine, and still others report starting
problems due to the higher compression making it harder to spin the engine.

And there are also plenty of folks who are happy with their high compression
choice...

Personally, I think you should talk with some shops who have experience in
this area. Lycon and Bart Lalonde (he runs an engine shop in Kamloops, BC)
come to mind. A google search should turn up phone numbers for both.

KB

"Ron Lee" wrote in message

...



Since I have to overhaul my O-360 engine I am trying to assess the
facts and old wive tales about using higher than 8.5:1 pistons. I am
not concerned about running autogas.

I fly at high altitudes. Usually 10500'-12,500' and up to 17,500'
when over the Rockies. My home airport is around 6,800' MSL with
density altitudes at take-off up to 10,000' in the summer.

My concern is whether up to 10:1 pistons reduces my expected TBO (2000
hours) or causes other problems.

Ron Lee- Hide quoted text -

- Show quoted text -

If you fly most of the time in high altitudes the higher compression
pistons will give you better performance. I am in the same boat here
in Jackson Hole Wy. My toy is sittin in the hangar at 6450 msl and I
always fly in the 11,000+ range. The only hiccup to higher comp
pistons is if you were to relocate down to sea level, then the motor
will be under some higher stresses, IMO the motor should live to TBO
though...

Ben
www.haaspowerair.com