G62 Muffler
 

Hi All,
I am in the market for a wrap around Pitts style muffler for a Zenoah G62. Does anyone Know how many RPM's are lost, if any, compared to open stack,with a Jtecwrap around?
I have anouther brand muffler and it knocks 500 RPM off the top. This is unacceptable for my application.
Has anyone tested the Jtec on a G62?

Jim

RE: G62 Muffler
 

Results from Dick Pettit who wrote for R/C report as reported to us at JTEC

Just a short note with some data I collected with the new Pitts muffler. You can use
this data and photos anywhere you like.

I was running a brand new Zenoah G-62 with an APC 22-10 wide blade prop and using the
stock canister muffler. I also converted it to electronic ignition using the CH RC-EXL
unit.

Once I had about one tank of gas through it, I made some RPM and sound measurements with
the following results:

Reliable idle speed - 1250
High speed RPM - 6650
Sound level at full throttle and 25 feet - 93 db

I then pulled the Zenoah muffler off the engine and replaced it with your standard Pitts
style muffler. Same prop, same gas, same day!

Reliable idle RPM - 1200
High Speed RPM - 7050
Sound level at full throttle and 25 feet - 93 db

No difference in sound level, but 400 more RPM, which calculates out to 4 more pounds of
thrust.

And it sounds great in the air on my 97" Gee Bee Model Y as it roars past.

Thanks again!



Dick Pettit

RE: G62 Muffler
 

Jim, I've been running a J-tec muffler for a few months now. I just tach mine last week with a APC t-6 racing prop . it was turning 7400 on the ground. I had a Slim line on it before and it would tach out at 7200/7300. This combo pulls my T/F Mustang around at 125mph. I am pleased with it's performance. However I've have a heck of a time keeping it tight at those rpms. The prop and spinner are balanced.
Hope this helps
Kelly

RE: G62 Muffler
 

T/bolt47

having run a pair of G-62 std mag congig for the last 7/8 years to keep all wrap arround mufflers tight add a third attach point on the oopsite side so they shake the same :D

Cheers Bob T