Thread Tools
Aug 18, 2016, 04:05 AM
Registered User
Thread OP

OS FS 70 muffler on OS FS 91.

I just found out that thread size of FS 70 and FS 91 is the same. I'm just curious what could possibly happen if I switch mufflers.

I have a plane that i wanted to keep clean and slick. My engine is OS FS91. I plan on putting OS FS 70 muffler on it. Just want to know what problems can arise if I do it.

Sign up now
to remove ads between posts
Aug 18, 2016, 06:24 AM
Registered User
Reginald's Avatar
less oily mess and a tad more silent...
Aug 18, 2016, 08:40 AM
Registered User
glidarflyar's Avatar
and the possibility of less power
Aug 18, 2016, 09:05 AM
Dieselized User
gkamysz's Avatar
According to my data, the same muffler was used for FS-70S and 91S. Are you looking at the later mufflers which were larger? The Suprass II series (black rocker cover) had larger mufflers, but were still the same for both displacements.

Aug 18, 2016, 09:39 PM
Registered User
Thread OP
Thanks. Yes, what I have is a bit larger. I'm curious about the oily mess.. because unburnt oil will come out no matter what right?

Quick Reply

Thread Tools