flyrotary@lancaironline.net Mailing List Archive

Message

I am curious Rusty about how easy/hard to start on a cool morning with the injectors 30" away. On my last manifold all 4 were approx 24" away and starting on a cold morning was a b----, I would sometimes use up the battery charge. Now all 4 injectors are approx 5" away from the inlet to the combustion chamber and it starts on the first turn or two of the prop.

Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC

----- Original Message -----

From: Russell Duffy

To: Rotary motors in aircraft

Sent: Tuesday, March 30, 2004 1:15 PM

Subject: [FlyRotary] Re: No rev-2 flying yet (Tracy, see comments in red)

This may occur because in one fraction of a second you are opearting at WOT (lots of fuel flow) and the next down to idle.

In thinking about this some more, it would make sense that I didn't have nearly the same problem before. In the rev-1 version, I had the primary injectors in the block, and the secondaries were only about 14 inches away. Now, all four injectors are about 30 inches away, so there's a lot more fuel left in the intake when you chop the throttle.

I agree with Tracy that this isn't my normal operating mode, but when testing the engine, I like to try everything I can think of, so there won't be any unpleasant surprised in flight.  FWIW, the turbo used to throw a nice flame out the short pipe when I'd chop the throttle, but I don't know if that would make it to the end of a longer pipe, through a muffler.

Rusty (off to test my O2 reading on the EM-2)