VetteV12

Does anyone know the max % of nitro to run in an Enya .90 4C with the head shim still installed at 4500ft elevation? I'm thinking 20% but want to be sure.

VetteV12

Afterthought, I run 20% in my OS 46AX II with out a head shim w/ a #8 plug and she runs like a champ.

1QwkSport2.5r

You will be very unhappy running 20% nitro in an Enya 4-stroke. They run just fine on 5% nitro. I have a 60-4C myself and have tried up to 20% nitro with unsatisfactory results. It's not an OS or Saito.

5-10% nitro, 20% oil is ideal IMO.

bogbeagle

Straight fuel is my preference.

jaka

Hi!
All Enya engines can be run on 5-15% nitro!Running them on 80/20 fuel is not recommended as the high speed needle setting will be very sensitive. Nitro is used for broaden the needle setting range so the engine will run at its best.
OS F plug is the plug of choice!

NM2K

My Feedback: (14)

It depends upon whether the engine is of recent or earlier design. And as has been said previously in this thread, one must adjust the compression ratio via the addition or subtraction of head spacing items, such as shims or head gaskets. Also the type and heat range of glow plug and the amount of load (propeller) makes a considerable difference in how one of these engines handles nitromethane.

My Enya R120C, 80 & 60 4C, 40 & 45 CX engines were happy with 0 to 5% nitromethane and not so happy on fuel with more nitromethane. Reducing prop load can sometimes turn an Enya engine with too much nitro in the fuel into a *****cat. But it is a waste of money.


Ed Cregger


P.S. Sorry. I have a sticky return key and it loads up a file with endless hard returns.

Altered1

The instruction manual I got with my Enya 60XF 2C says they will all (2C and 4C) run quite well with 0-10% nitro.

personal preference and application have a large part to play in your fuel selection.

1QwkSport2.5r

For some reason, many people here in the US are nitro happy in that they feel compelled to run 15-20% nitro in everything. Some find out the hard way that some engines like Enya and SuperTigre don't like a lot of nitro.

I did an experiment with my Enya SS30 using 5, 10, and 15% nitro and noted the rpm. 300rpm gain from 5% to 10%, and 200rpm gain from 10% to 15%. With a 4-6$ difference per gallon, it's hardly worth wasting the extra nitro IMHO.

My 60-4C instructions say 5-15% nitro but I got no worthwhile rpm gain from 5% to 20% so I stick with 5% nitro and 20% castor. I'll try FAI fuel next summer to pinch a few pennies since most of my engines will run nicely without any nitro at all.

VetteV12

The more $$ for nitro isnt a concern since I get it at $30 gallon because I buy in bulk. I just want to get the most out of this engine.

1QwkSport2.5r

Then you will need head shims and cooler glow plugs. The older Enyas are setup for low nitro. If you want an engine you can feed a ton of nitro to out of the box, get an OS or Saito and sell the Enya.

TFF

The use of the Enya is not like you would use a Saito on a profile hovering 3 ft off the ground. It is actually an early attempt at a 4 stroke pattern engine that soon was increased to the old 1.20 limit. It is good for scale and sport pattern planes not screaming low pitched props. It is like a bank vault Mercedes 4 door not a rice rocket sport bike.

VetteV12

Yes I understand that and I wouldn't put a 4stroke anything into a plane I wanted to speed around with; that's what a 2stroke is for. I simply wanted to know max nitro% for best power results; never said anything about going down to small high pich prop and screaming around. How did this thread go from such a simple question to accusations about what I want to use the engine for...?

1QwkSport2.5r

No accusations intended, but based on the above quotes, One would assume you planned to use 20% or more nitro in your Enya 4-stroke. To those "in the know", using that much nitro in an Enya 4-stroke is useless and will most likely make the engine unreliable. You asked what the max nitro content for that engine is, and we told you.

If you want to get the most out of the engine, run no more than 10% nitro in it and use plenty of oil - 20% is good.

BUT this is my opinion. If you want to try running 20% nitro, go right ahead. Its your engine. If you shim it properly, it will handle it fine. Out of the box, it probably wont for very long, especially if its never run before.

TFF

Most people who are willing to buy 20/30% are after the nth degree which is asking a high performance question; that is why you are getting the answers. I run 15% Omega in my YS just as happy as with 20/20. I dont need to run more than 10% in anything else or it needs a bigger engine. All Enyas are 10%ers unless you have an old F1 race engine. They are forgotten engines because they dont play the HP race like OS and Saito.

David Bathe

I've run 15% on my Enya .41 4stroke for a decade plus and never had the slightest problem.

proptop

My Feedback: (8)

In the 1st post the O.P. says he's at 4,500' altitude...

(Where I fly, we are at approx. 500'...I don't have any experience w/ flying fields over 1,000'...and I never ran anything but 10% Nitro in my Enya .80-4C )

Would the 20% Nitro he's talking about help to bring back some of the "lost" power because of the higher altitude/less dense air?

Isn't an engine's effective compression ratio lowered by the less dense air at higher altitudes? IOW maybe the 20% Nitro would be O.K.

bogbeagle

There is sense in what you say, since Nitro is a form of "chemical supercharging".

As so often happens, there's no real answer to the OP's question. It's mostly just a matter of personal preference.

VetteV12

This is what I was trying to get at when I mentioned the high altitude. I'm not all that educated on how the nitro works besides the fact that it adds more oxygen and thats why its better for the higher % at the higher altitude. So I was trying to get a feel for whats best so I don't blow it up. Basically with info I've recieved here it's a toss up and to just use whatever I see fit and whatever makes it run.

proptop

My Feedback: (8)

If it was my engine, I would experiment with plugs and prop load...
Choose the prop carefully to not over load it...listen carefully while in flight...maybe fly a flight or two alone, w/ nobody else in the air at the same time so you really can hear what's happening.

What plug and prop would you decide to run?
I would typically say something like an Enya #3 or O.S. F and a 14x6 or maybe 15x4 or 15x6 at my altitude...

VetteV12

15x6 and original Enya plug or a Merlin plug if the Enya burns out. I bought one of each heat range from him for 4stroke and 2strokes, only for airplanes though.

VetteV12

After getting back from the LHS I will have to try 15% O'Donnell that has 18% oil with castor/synthetic blend because the LHS is out of everything else and I don't plan to buy more in bulk until the 2 remaining gallons I have are gone. Wish me luck.

MikeG4936

My Feedback: (5)

Mine ran great on Omega 10% and a 14x6 prop