Hi Mike,

Randy is out to the NATS and he may take some time to answer this.

But I am curious about your findings with the APC 13x4W.

If I am not mistaken in the Enya manual they say the engine like to run 11 to 12 thousand rpms with a composite prop for fly wheel effect.

After I email you, I was advised by an expert to avoid APC props, he warned me that they can break and recommended using Zinger Pros instead. I am worried because I like APC after carbon fiber props.

Good luck,

Martin

Hi Mike

I would suggest first  starting with an Pro Z 13 x 5, this is a good all around prop for that motor.

Regard
Randy

Hi Randy,

I hope you and my other friends are getting some good air at the NATS.

I tell ya we have tested one Enya 61CX that must be very special motor then, or you didn't tell me the muffler you sent me had a turbo installed on it!

The Zinger Pro 13x5 didn't load the engine enough by far, we had to needle it very very rich to keep laps at 5.2s and it burps like a FOX 35 in the inside corners, so much so that it seems almost to stop the model in the air. Amazingly is that the engine never ran away and it kept the needle setting perfectly through out the flight no matter if extremely rich, very rich or when it was right on the money.

Using the 13x5 zinger pro and setting the needle where the engine ran smooth we were getting laps around 4.6s and that was with a draggy B.W P-47 with over 70oz.

This engine was sold and later used on a Strega that Windy flew here in Brazil. Windy made several positive comments about it, even though it was not set in the best way. For lack of proper advice Raul end up getting a B.E 12.5x5.5 3blade and of course his Strega went ballistic. He had to set his lines  71' eye to eye to get laps at 4.9~5.0s. Still he had to launch extremely rich, so rich that the engine would quit in the inside corners with a T.B Plug, only an Enya 3 kept it running. At this contest he flew in some pretty strong and turbulent wind and the Enya 61CX pulled the Strega like it was a toy,  but with a very wild 4-2-4 run.

The best and smoothest run I have seen this engine do was with a Bolly 13x4.5 3 blade prop, 8.0mm venturi, 10% Nitro 22% oil and with your tube muffler. The prop had a 3.7~3.8 pitch and ohhh the  4-2-4 was so nice and it kept the P-47 flying precisely.

Martin

Martin,  hope you guys remember that line length is 70 feet max center of plane to center of handle.  A few guys were upset at the NATS when told they had to cut their lines.  I know a lot of contests just figure everyone knows the rules.  Also have you tried a different fuel with more oil or less nitro?  Another thing is to choke the venturi down a little so you are not getting so much power.  There are so many things to consider when trimming planes.  Have fun and keep us posted,  DOC Holliday

you bet! As matter of fact Windy said the same thing. We also know that flying with shorter lines it would be much better, it was one of those things that you do in a hurry to get it going. After that contest we tried to get the right props from Bolly and B.E , but it was too late and he decided to sell the Strega. I was glad he did because I beat him easily in the last two contests and before he was always 2 positions at least ahead of me

The Strega/Enya 61 is with a higher skilled pilot now, and his score went up with it. He had a Skywriter /ST 60 before and confirmed the Enya 61CX is a far better engine, no comparison, it is an different class of power and performance. The Strega seems nothing for the Enya 61CX; now the old ST 60 could not handle the Strega with any authority.

For lack of other props , his setup is even worst, in my opinion. He is using a Bolly 12.5x.5.5 2B depitched to 5 if I am not mistaken, fuel with 0% nitro and 25% all castor.  He is complaining about the strong burp in the inside corners. But is very happy with the engine run overall that is much better then an ST60. I have urged him not to run all castor in this engine, but he doesn’t care. I am sure eventually his engine will not performing as well.

I sent him an APC 14x4W for him to try but haven't heard anything back from him. I will also try to get Zinger Pro 14x4 and JXF 14x4 to try.

BTW, I own the only hobby shop dedicated to Stunt products in Brazil, so that’s why I am always involved in helping others getting products down here.

Martin

Hi Martin:

Flew the Score yesterday and today with Zinger 13x5 (regular square tip Zinger, not "Pro"), Sig 10-10-12 fuel, temp around 75-80F, launch rpm 8600-8900. Nice solid runs. I did change out the Enya plug to a Thunderbolt idle-bar RC plug which improved things. Wind got too blustery to try the Mejzlik 12.5x5.2 3-blade, so that will have to wait till next weekend. If the engine appears to want more revs I will try the 12.5x4.5 3-blade. I will report back after the next round of experiments.

Hi Martin:

I am using the Randy Smith tube muffler, very little resistance. Actually I use that muffler on most of my engines. The Enya 40ZXP (which I have run in but don't have in a plane yet) comes with a nice fairly small muffler. I don't like the noise level with a tongue muffler.

The Mejzlik prop is mounted on the 61. I will try it this coming weekend.