Trying to get more hp out of a 165hp Franklin?

KENDRURY · Post by **KENDRURY** » Thu Jan 13, 2005 3:16 am

Has anyone ever put high compression pistons in a 165hp Franklin to get an extra 15hp out of the engine?I heard you need three items to get the 15hp,first bigger intake manifold pipes(220 hp pipes?),second a bigger jet in the carb and third the high compression pistons?
I would appreciate any comments.

Thanks,

Ken.

Post by **GAHorn** » Thu Jan 13, 2005 10:01 pm

Sounds pretty illegal.

blueldr · Post by **blueldr** » Fri Jan 14, 2005 4:22 am

If my memory serves, I believe the Franklin engine compression ratio is already somewhat higher than the Continental 300 cu.in. series of engines. Changing the pistons to a part not certified in the engine would nulify the engine certification. That would be OK in an experimental registered airplane, but it would be strictly a bootleg job in a C-170. And you know how the FUZZ is always out tearing down suspect engines to check part numbers on the heads of pistons.

Indopilot · Post by **Indopilot** » Fri Jan 14, 2005 4:29 am

Don't know about Franklins but have been told by a guy that did it, that putting C-85 domed pistoms in our O-300's really makes them sit up and snort. But like you say George, it would be sick bird (ill eagle)

not to mention probably agravate the cracking problem the old 0-300 cylinders have. Brian

zero.one.victor · Post by **zero.one.victor** » Fri Jan 14, 2005 6:58 am

I hear the C-85 piston is one of the tricks the Formula 1 guys do to the O-200's for racing. works for them.....of course, they're not too concerned about TBO. I have heard that some of the Swifters also do this with the 145.

Eric

davevramp · Post by **davevramp** » Fri Jan 14, 2005 11:06 am

Looking for technical information on c145 or o-300.
How much does the c-85 pistons increase the compression ratio for
static and dynamic? What is the combustion chamber volume?
I do not want to try to reinvent the wheel. Any help would be appreciated.
Thanks
Dave

zero.one.victor · Post by **zero.one.victor** » Fri Jan 14, 2005 4:10 pm

Seems like the best place to get "soup-up" information (for reference only, of course!) would be from the Formula One crowd. Maybe there's some websites or club forums? Or else from an engine builder who does Formula One O-200's.

Eric

KENDRURY · Post by **KENDRURY** » Sat Jan 29, 2005 5:15 pm

ak2711c · Post by **ak2711c** » Sun Jan 30, 2005 7:23 am

Get ahold of Lycon in California. There specialty is building souped up experimental race engines for airplanes. You name it and they have done it. They also do have some legal performance enhancers for some engines.
Shawn