quote:

ORIGINAL: blw

Bill,

I don't know if mine worked on those or not. I remember him working on Corsairs but I was too young to remember much of what he said about it.

quote:



I wasn't referring to the Enya .61CX engine's stroke. I was referring to the small gas passages inside of the crankcase because of the crankcase's .40 size lineage. Therefore, my statement was NOT false.


Ed Cregger

quote:

ORIGINAL: Taurus Flyer

Gents, for who is interested,

I read some posts about carbs,

Ever heard of the recovery of pressures of measuring orifices and venturi’s?
My attempt to realize a better sucking pressure recovery and lower carburetor resistance of my ENYA 60 4C engine. Enlarge the bore of air inside and outside of the barrel, equal to the bore/diameter of the carb housing and reduce the surface of the nozzle.
Maybe you think, the turbulence is needed to mix fuel and air, but too much turbulence is resistence, drag.

As normally I use a separate fuel pressure controller to supply the carb. So ratio of fuel and air mixture is no problem.

You see some pictures of the normal barrel and modified one.
I also did give the modified barrel a direct fuel connection to have a better control of the right flow direction, one way, to the nozzle tip.
Result is of course the fuel hose tube does rotate the degrees of the barrel but that’s no problem The separate needle valve is mounted on a place I can handle easy.
Engine runs fine for many flights now.

I use the 30 years old engine in a modified Orion, see last picture.
The plane is in the repair shop to fix the wing. It had a date with a Spruce Choose spar in the field, nothing to do with the engine.

Cees

quote:

ORIGINAL: martin_solo

quote:



I wasn't referring to the Enya .61CX engine's stroke. I was referring to the small gas passages inside of the crankcase because of the crankcase's .40 size lineage. Therefore, my statement was NOT false.


Ed Cregger

Ed,

Please accept my appologies, I was bad .

I never thought about transfer ports sizing. But now I am curious, how smaller is the Enya 61CX transfer ports compared to a regular 61?

I think the stock carb is too small for this engine, it is the same used in the Enya 32CX. It could run much stronger with a bigger one, like the G8.

Martin

quote:

ORIGINAL: martin_solo

message shortened by Taurus FlyerCees,

I like to hear this modification stories. A friend of mine also made different venturi for his 4S engine, but for use in C/L, and his aproach was also in the direction of a cleaner and less turbulent passage. Regular Venturis for C/L has the Spray bar crossing right in the middle of the venturi, he made one with the NVA tangent to the venturi inner wall, purtruding about .020'' inside the venturi, it work better then other venturis.

One experiment I would like to see you try is to make the nozzle shorter, so it is just about of the venturi wall, that should make even less turbulance.

Martin

quote:

ORIGINAL: Taurus Flyer

quote:

ORIGINAL: martin_solo

message shortened by Taurus FlyerCees,

I like to hear this modification stories. A friend of mine also made different venturi for his 4S engine, but for use in C/L, and his aproach was also in the direction of a cleaner and less turbulent passage. Regular Venturis for C/L has the Spray bar crossing right in the middle of the venturi, he made one with the NVA tangent to the venturi inner wall, purtruding about .020'' inside the venturi, it work better then other venturis.

One experiment I would like to see you try is to make the nozzle shorter, so it is just about of the venturi wall, that should make even less turbulance.

Martin

Martin,

The engine of your friend probably did not have a throttle, because you write C/L, ''control line''.
For me a constant fuel air ratio over the power range is more important than max power so also in idle position I need an airflow over the tip of the nozzle which I give a special shape. For this reason I have to position the tip in the centre of the venture and barrel. When I make the nozzle short it will be in a dead corner of the barrel in idle position.

Cees

quote:

ORIGINAL: martin_solo

Ed,

You better get your Enya 61CX out of the box and start using it to make a better evaluation of its performance. I actually thought you had measured the transfer ports, so again I am going back to say you are making false statements

I don’t have any 61 here to measure against the 61CX, but I have an OS 55AX, the transfer ports in the Enya 61CX looks about the same area. The crankshaft in the OS 55AX has a 8.7mm bore and the Enya 61CX 10.6mm.

The 55AX carb is 7,6mm and the Enya 7,4mm

A bigger carby with 8.00mm should work fine on the 61CX.

There is a lot of metal left to machine a bigger transfer port in the Enya 61CX, but why Enya didn’t make it, is it really necessary?

Martin

quote:

ORIGINAL: Taurus Flyer

quote:

ORIGINAL: martin_solo

message shortened by Taurus FlyerCees,

I like to hear this modification stories. A friend of mine also made different venturi for his 4S engine, but for use in C/L, and his aproach was also in the direction of a cleaner and less turbulent passage. Regular Venturis for C/L has the Spray bar crossing right in the middle of the venturi, he made one with the NVA tangent to the venturi inner wall, purtruding about .020'' inside the venturi, it work better then other venturis.

One experiment I would like to see you try is to make the nozzle shorter, so it is just about of the venturi wall, that should make even less turbulance.

Martin

Martin,

The engine of your friend probably did not have a throttle, because you write C/L, "control line".
For me a constant fuel air ratio over the power range is more important than max power so also in idle position I need an airflow over the tip of the nozzle which I give a special shape. For this reason I have to position the tip in the centre of the venture and barrel. When I make the nozzle short it will be in a dead corner of the barrel in idle position.

Cees