Author Topic: Blank (Read 1140 times)

Rusty · « **on:** June 03, 2021, 12:50:31 PM »

Blank

Martin Quartim · « **Reply #1 on:** June 04, 2021, 03:09:22 PM »

Quote from: Air Master on June 03, 2021, 12:50:31 PM

Hello,

I got an Enya 40, 6002 off ebay for 15.00. It was dirty, but I have cleaned it up and it is a nice engine.

I need to make a venturi for it. The best I could find is the ID should be 7.5mm. Is this correct for this engine. It is a single dykes ring version.,

Thanks

7.5mm is what I use with my Enya 45. But venturi size depends on the model, prop, nitro%, altitude, climate ....

I read somewhere that this Enya 40 6002 is stronger than the 45s and likes to work at higher rpms, so I guess 11x5 and 12x4 props should work best.

You can go with a smaller venturi and then make it bigger, or use a bigger venturi and if necessary restrict the airflow with an air filter which is always nice to have.

Good luck!

Martin

Brett Buck · « **Reply #2 on:** June 05, 2021, 02:31:46 PM »

Quote from: Air Master on June 05, 2021, 10:13:03 AM

Thank you for the info.

Note that the difference between 7.0 mm (.276") and 7.5 (.295") is *massive*, a huge difference - using a .157 spraybar (4.0mm), it goes from 0.0189 square inches of choke area, or 0.0243 square inches. ** 33% more ****. That is nearly the entire range of usable systems for stunt. You are much better off starting smaller and working up, because it will at least make it needle properly. If, when it's otherwise working OK, and you want to adjust the power slightly, you might go up by ** 0.1 mm ** ( .004"). That will take you 0.0189 square inches to 0.0199 square inches.

Venturi size is a very sensitive adjustment, you need to think of it in a single-digit thousandths of an inch, not tens of thousandths, and tenths of a mm, not 1/2 a mm.

Brett

Martin Quartim · « **Reply #3 on:** June 06, 2021, 08:42:58 AM »

Quote from: Brett Buck on June 05, 2021, 02:31:46 PM

Note that the difference between 7.0 mm (.276") and 7.5 (.295") is *massive*, a huge difference - using a .157 spraybar (4.0mm), it goes from 0.0189 square inches of choke area, or 0.0243 square inches. ** 33% more ****. That is nearly the entire range of usable systems for stunt. You are much better off starting smaller and working up, because it will at least make it needle properly. If, when it's otherwise working OK, and you want to adjust the power slightly, you might go up by ** 0.1 mm ** ( .004"). That will take you 0.0189 square inches to 0.0199 square inches.

Venturi size is a very sensitive adjustment, you need to think of it in a single-digit thousandths of an inch, not tens of thousandths, and tenths of a mm, not 1/2 a mm.

Brett

I use to be good in Thermodynamics and Fluids Dynamics, but this was in the 80s. I am too lazy now to do the math work, but perhaps you can figure out what is the real Power increase when changing the venturi diameter. I have a feeling that power increase is not directly proportional to area increase.

I have never used another venturi on my Enya 45 6001 other than the 7.5mm one. But I have tested venturies from 7.5mm to 9.0mm in my Enya 61CX and it seems to me that changing 0.5mm did not make my engine run that much stronger. Enya offers optional venturis in 0.5mm increments and so far seems to work quite well for me.

Martin

Brett Buck · « **Reply #4 on:** June 08, 2021, 09:43:08 PM »

Quote from: Martin Quartim on June 06, 2021, 08:42:58 AM

I use to be good in Thermodynamics and Fluids Dynamics, but this was in the 80s. I am too lazy now to do the math work, but perhaps you can figure out what is the real Power increase when changing the venturi diameter. I have a feeling that power increase is not directly proportional to area increase.

I have never used another venturi on my Enya 45 6001 other than the 7.5mm one. But I have tested venturies from 7.5mm to 9.0mm in my Enya 61CX and it seems to me that changing 0.5mm did not make my engine run that much stronger. Enya offers optional venturis in 0.5mm increments and so far seems to work quite well for me.

Martin

At some point it gets so big that it doesn't work any more because the venturi stops being the limiting factor. The entire idea is to get it into the zone that adjustments do what you think and the power is roughly proportional to the choke area. What I am concerned about is starting out so large that it won't needle. It's far easier to get it working starting small enough to find any other issues and work up, than it is to work it down.

Brett

RandySmith · « **Reply #5 on:** June 09, 2021, 12:24:15 PM »

Quote from: Air Master on June 03, 2021, 12:50:31 PM

Hello,

I got an Enya 40, 6002 off ebay for 15.00. It was dirty, but I have cleaned it up and it is a nice engine.

I need to make a venturi for it. The best I could find is the ID should be 7.5mm. Is this correct for this engine. It is a single dykes ring version.,

Thanks

The normal usable range for that engine is from .265 to .285, Some may use a step smaller or a step larger, but you would be best served trying in that range. I set them up with 265 or 275, depends on what muffler and how they are going to use it.
Try to stay away from MM huge jumps , as .005 will make a very noticeable difference

Randy

Author Topic: Blank (Read 1140 times)

Rusty

Blank

Martin Quartim

Re: Venturi size for Enya 40, 6002

Brett Buck

Re: Venturi size for Enya 40, 6002

Martin Quartim

Re: Venturi size for Enya 40, 6002

Brett Buck

Re: Venturi size for Enya 40, 6002

RandySmith

Re: Venturi size for Enya 40, 6002