Can someone chime in and confirm something?

On the Evolution (.46) for an H9 Alpha, is an A3 glow plug a suitable replacement?

My LHS has stated that these "should" be good. I'd just like some confirmation that these'd be adequate.

Thanks

Yes, an A8 is preferred, but the A3 will work just fine

I'd heard that the Evolution 2-strokes respond and transition best with really hot plugs and that the A3 was actually ideal.

Hi!
There isn't such a thing as "best plug"! It all depends on what prop and fuel you use and what compression ratio you have (You have head shims to remove if you want to have more power).
An OS 8 or Enya 3 will work fine in all two stroke engines running 0-15% nitro.

So what's the difference then between an A3 and and A8?

Based on what my LHS stated, I bought two A3s. Am I in trouble with that?

The A3 is Hot.. the 8 is medium... I believe the colder the plug the worse the idle.

Question for anyone who knows... Are the hotter plugs usually used for 4 strokes since they need to hold heat during the non-power stroke?

Actually ALL of my Evolutions came with "long" plugs.

Check out this picture.



From left to right: Stock Evolution 2 Stroke Glow Plug, O.S. "F" 4 Stroke Glow Plug, Stock SuperTigre .75 2 Stroke Glow Plug, O.S. A3 2 Stroke Glow Plug


I've seen the A3 & A8 recommendations given, but I've found that from the PTS engine up, the Evolutions run best with the long plugs.

You can substitute the OS "F" plugs or other similiar long plugs such as the SuperTigre, etc.

Hotter plugs help at idle but can cause pre-detination at higher RPM.

Hotter plugs maintain their heat for a longer period of time, so they are usually needed for 4-strokes and will help some 2-strokes idle and transition. So, yes to what KitBuilder asked.

As for being in trouble with the A3? No, not yet. You have the plug, put it in and run it and see. If the engine doesn't idle or transition well, or doesn't produce the RPM it used to, or you hear a frying egg sound while it's running, and the engine didn't do any of that before, then maybe the plug is the issue.

I don't know why OS makes their plugs shorter than just about everyone else. Some Evolution engines I've run into have been helped by a hotter plug, but I actually run mine on a K&B 7300, which is a colder plug. But I'm using 15% nitro, took the baffle out of the muffler, and run an APC 11x5 prop, so I need a colder plug.

The stock Evolution plug appears to be on the hotter side, so if you want to use an OS plug, I'd start with the A3, but plenty of guys here use the #8 just fine in their Evolutions.

Frankly, unless you're either trying to maximize power output or running high nitro or really low nitro, or have played with the compression ratio of the engine, most of the medium to medium-hot plugs will usually work fine.

It does sometimes vary with the engine though. I've seen two brand new Evolution .61s on Alpha 60s actually seem to like differnet plugs. I think one was particuarlly tight in compression, but I'm not sure (didn't spend that much time playing with it, just got it running and went back to getting the student into the air).

Hi,

I have a evolution .46 also, glad to get the info.

hope this is not out of line, but here goes. Minnflyer, when we were at the toledo show you told me how to set the carb on the evolution .46. Could you give that to us, I would like to save it just in case.
seeings as how there more than one of us here with one,should be of help.

enjoyed meeting you , hope to see you guys next year.
thanks
sticks

I have 2 evolution .46 engines and I use Miracle plugs on both, thay can be used on four or two stroke, they idle very well, transition is excellant. Running 15% cool power.

I would like to see it also

Yup, Miracle plugs ARE "long" plugs too, and I've had great success with them on the Evolution engines.

All my engines are Evolution, I own a .46NT, a .46NX and a .60NX. I run a O.S.#8 short plugs in all of them and I have no problems at all. I only use the stock long plug for the engine break- in, then after that I toss it in the trash and put the O.S. # 8 short plug in.

If you have any questions, look at the graph below... it will give you an idea what to use.



I run a #8 so my engine won't over heat when the weather temps hit 90*. My Evolutions don't like hot and humid temps with a #3, so I run the #8... I've had less "Dead Sticks" as a result.

A short plug or long will not make a difference on how the engine runs from my experience.

I hope I helped.

A long plug tends to help with inverted engine positions.

The Evolution designers utilize long plugs, so I would assume that they know what they are doing.

I don't know about the long plug helping with the inverted engine because I don't invert my engines often.


All their 2 Stroke Glow Engines are long pluged from the factory incase you didn't know... so maybe too Evolution, it doesn't make much or any to list it? I called Horizon and they said it doesn't make any difference or it would have been noted in the manual.