G8-2-130R engine with 90 degree bend

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G8-2-130R engine with 90 degree bend

Post by zoltans » Sat May 21, 2005 5:08 am

I recently attached a tube made of thin sheet steel to the tailpipe of the
130R and I ran it. This extension consists of three segments, each
implements a 30 degree bend. After the first two there is a short straight
section followed by the third bend. There is also a straight section after
the last bend. There is no fishtail cut in the end.

I hooked up the engine to a 5 gallon black propane tank that was upside
down to get liquid.

The engine ran fine just like before when it did not have this extension.
The sound level was 115 dB at 30 feet from the engine.

I recorded video and sound. I had to turn the engine off because I had
a propane leak. Only ran it for 10 seconds.

I put the sound on an oscilloscope. Here is what it was:

An approximately sinusoidal waveform at 133 Hz frequency.

Superimposed on this sine wave there were two pulses. On the increasing
pressure side about the zero crossing there was a sharp strong high
pressure pulse. On the decreasing pressure side also around the zero
crossing there was a smaller pulse, which was sometimes just a little
noise, like a squiggle, and sometimes it was a well formed pulse about
half the size of the big pulse.

This might help some people figure out what the engine is doing.

I fixed the leak, will run the engine again and get thrust data. I will post
the data here.


jerry marra
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re: G8-2-130R engine with 90 degree bend

Post by jerry marra » Sun May 22, 2005 6:30 pm

Thank you very much for the data,I would be interested on you thrust level test.
A few post back that was my ?? regarding the 90 bend to all and ERIK but no one at that time tried it ,so thank you for the info.
Im surprise that the exhaust node close to the three stages did not affect the intake LOCK.


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re: G8-2-130R engine with 90 degree bend

Post by kreon » Mon May 23, 2005 1:56 pm

Great job and thanks for everything to date!

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