RE: Why (an Enya 11 CX D) Diesel?
 

The instructions for the ENYA Ultra 11 CXD recommend that users select a 9x4 or 9x5 prop for R/C use.

Good thrust, with low noise.

I have no doubt this engine would be happy spinning a smaller prop at higher RPM's, but I am little over screaming small displacement two strokes.

That said, FlyingKiwi metioned to me yesterday that a Rothwell R 320 will spin an APC 7x7 at 18,000 RPM plus! ... not too shabby for a non schneurle Olly Major Replica, if that's what moves you :D

RE: Why (an Enya 11 CX D) Diesel?
 

I'm surprised that no-one here has mentioned the fact that the earlier Enya CX 11's had the high tech AAC piston & liner, whereas the later (current) ones have the much heavier (and cheaper to manufacture) ABC set-up. Enya's AAC technology is miles (kilometres?) ahead of ANYONES ABC, so the early ones are worth looking for. BOB

RE: Why (an Enya 11 CX D) Diesel?
 

Wow... I did a little sleuthing to fine out what an R 320 was. I shudder to think of the cost after spending several weeks pay on Schlossers and spares this fall. If the R320 could be had with a muffler and carb it would really be something special to me. I don't live anywhere that an unmuffled engine that size would run long without a call to the police.

RE: Why (an Enya 11 CX D) Diesel?
 

Dave
no R/C or mufflers,
Prices are in Australian dollars

R100 $250

R150 $350

R250 $375

R320 $375

Post to is $15 per engine

RE: Why (an Enya 11 CX D) Diesel?
 

The R320 is NOT a Olly Major replica. It's a development of the R250 with stretched bore and stroke. Oliver made several batches of .19's as well. They were also based on the 2.5cc Tiger. The Major is a completely different engine and was never a racing engine.

Dieselbloke

RE: Why (an Enya 11 CX D) Diesel?
 

For those who don't know here is Steve Rothwell's engine site -
<a href="http://www.smrpl.com.au/page2/page2.html">http://www.smrpl.com.au/page2/page2.html
</a>
Simply the best engines of their kind, period.

RE: Why (an Enya 11 CX D) Diesel?
 

Hear, hear!
Peter

RE: Why (an Enya 11 CX D) Diesel?
 

[:@] Thanks gents, I am corrected ... what I meant to say is it was designed to compete with a PAW 19 TBR in combat spec ... please accept my apologies! Not sure where I got the idea it was a major rep from.

RE: Why (an Enya 11 CX D) Diesel?
 

Here's an exerp from a test done when the SS .15 Diesel came out (A lower revving unit according to the Enya site)

"Performance fits the purpose?

Test results gave a rather flat power ouput curve peaking at a modest .19 BHP at around 12500 RPM,while torque dropped off steadily with increasing revs. A subsequent look inside showed nothing was amiss and all the "numbers' suggested a higher power output potential.

A second series ot tests confirmed the dramatic performance improvement with peak power output Doubled to just over 0.4 BHP at a little over 17,000 RPM.

Unlike diesel engines of old, the Enya does it all with minimal vibration, even at speeds to 20,000 RPM"

I have to add that the second test was done with a larger venturi which is about the same size as the one on the R/C Carb. Nonetheless, the H.P was achieved at much higher RPM's.

Don't forget that the 11 CX was originally designed as a high revving car / buggy unit. I have a "Spankin" new one coming in fresh from Japan in the next couple days, I'll try it out and let you guys know..

RE: Why (an Enya 11 CX D) Diesel?
 

Actually, what I like about high revving engines is that you get a lot of flexibility for different applications.

As mentionned, using a very low pitch decent size prop you get really good thrust as thrust is mainly a function of diameter X RPM's. I get above 32 ounces of thrust using an 8 X 3 prop on a glow Enya .09, enough to hover / torque roll / climb straight up on a 28 ounces plane (It revs it 15500 RPM static).

Conversely, if I want speed out of the same engine for another application, I just slap-on or a 7 X 5 (or smaller) and let her rip..

Finally, If I want to slow everything down and get (A little) quieter, I just load it up with a bigger prop.

My other Diesel, a PAW .60 TBR has only one speed: Really slow and quite frankly, a disapointing ability to produce much thrust or speed. I have tried just about every prop under the sun from 11 inches to 15 and about 7 lbs of thrust is the best I ever got. I wish I would have bought a higher revving MVVS .60 Diesel instead, that would have been a much more useful engine for me.

RE: Why (an Enya 11 CX D) Diesel?
 

G'day R/C Phile

After a good experience with the PAW .40 R/C (surprisingly powerful for a very traditional engine), I tried the PAW .60, with the same disappointing result. Somehow the "magic" in the .40 unit did not migrate to the PAW .60 MkII. Nice green anodised head though.

I do like my MVVS "long stroke" Schneurle .60 DFS, which I bought to replace it. Sold my .60 PAW soon after. I believe that Mr Carlson describes the .60 size "daddy" PAW as a "big friendly lump", which pretty much sums it up.

Let me know what you find with your ENYA Ultra .11 CXD. I am happy to throw on a 7x6 or similar on mine and spin it up again, to make my "rev jockey" friends happy. It's nice to experiment, even though screaming two strokes are not really my thing.

RE: Why (an Enya 11 CX D) Diesel?
 

A bit off topic, butIhave heard the same thing from many sources about the PAW 60 and I would think that the design has pushed the limit too far with a cast iron piston in a 10cc engine.
The PAW 40 Ihave seems very strong and has threatened to pull my portable test bench over more than once!

Back to the high revving diesels, Irather like the sound of a screaming diesel on a small prop as it masks the misfires most engines make.
(Ever seen a Rothwell R 250 zip around in the air? Blood curdling sound indeed.)

RE: Why (an Enya 11 CX D) Diesel?
 

Three of them together pulling 16k rpm on 7x7 props just magic!!

RE: Why (an Enya 11 CX D) Diesel?
 

I thought this was a little odd topic so I've gone through my papers on these engines and there seems to be three different versions, i.e. three different sets of cylinder and pistons. Notably the one for the Diesel is specifically marked as being only for the diesel version. Seems to me like they may well have changed the timing/ports of the diesel version as there is no real reason to change anything, with the counter piston being positioned in the head and all.

Anyway here are the three different versions with their respective cylinder-piston assembly numbers:

Enya 11 CX (Al-chrome and 1.79cc): 11CX04
Enya Ultra 11CX (brass-chrome and 2.09cc): U11CX04
Enya Ultra 11CXD (brass-chrome and 2.09cc): U11CXD04

When you think about it, if they were to produce a high performance diesel engine from their other small engines it kind of make sense to use the twin ball bearing, twin needle carb, ABC engine and just tweak the timing a little...

There are also three different crank models but from what I can see there is not an exclusive diesel crank.

RE: Why (an Enya 11 CX D) Diesel?
 

Found my little stash of NIB Enya engines, not really a collector but the 09 glow ones that I'm using and flying just never seems to wear out...

RE: Why (an Enya 11 CX D) Diesel?
 

I had a closer look at my engines and there is a clear difference in the ports between the 11CXD (AAC) and the 11CXD Ultra (ABC), but I cannot find much difference between the glow and diesel version of the Ultra. I can't really be bothered to do a full measurement of the timing on all three engines, but I've measured the exhaust timing. Seems fairly modest for all three to me;

Enya 11CXD (AAC); 140°
Enya Ultra 11CXD; 145°
Enya Ultra 11CX; 145°

Don't know if will show up well but here are images of the AAC and ABC for comparison;

RE: Why (an Enya 11 CX D) Diesel?
 

There is another big difference between glow and diesel, and that is the carburetor intake diameter. The glow version has a barrel opening of 5.5mm (about 7/32") compared to 4.2mm (1/6") for the diesel version. So all in all the diesel version reminds me a bit of the Irvine .20D, a strong built ball-bearing ABC engines that are most happy at moderate rpms 10000-12000rpm inspite of their high revving appearance.

The .11CXD could perhaps be made to run at higher rpm's ,since they are strongly built, but it may well require a larger carb. Much like the Enya SS.15D that appears to really come alive on the larger glow ventury.

RE: Why (an Enya 11 CX D) Diesel?
 

Hi all

I'm new to this forum. Can add my experience with the Enya 11CX in diesel form. We used them in Mini Goodyear - converted to diesel using a head from Nelson 15D machined down to suit Enya's smaller bore. Then drill &amp; tap the crankcase to accept six mounting screws, make some shims to adjust chamber volume &amp; there it is. They were soundly beaten when the OS 10 pylon special came out, but for a while, it was good fun.

I did eventually get around to testing my engine (for the record). It has a Cox carby fitted - drilled to 4.0mm bore. Peak power was 0.48BHP at around 21,000 RPM, which is quite good for a diesel of that size, especially remembering that the design is around 30 years old.

We did find that in diesel form &amp; pushed for max performance that the 3.5mm wrist pin would break. Easy enough to ream out the piston bosses &amp; fit a 4mm pin. Enya machine the circlip grooves deeper than they should really be, so no problem with the larger hole &amp; circlip fit. 

In terms of exhaust port ( and intake or transfer port) timing, there's no need to change anything. Yes, used them in glow format too in C/L Speed models &amp; in their day, they were tops.

Enya use the same alloy for both piston &amp; cylinder in the AAC setup. Around 16% silicon according to my spectrographic analysis back in the early 1980's. That's OK in glow form, as you can get by with a slack fit when cold &amp; still start it fine &amp; then the piston expands up to a good working fit at running temperature. Not so as a diesel if you want first-flick restarts. We'd selectively fit pistons in cylinders to arrive at a good diesel fit, but they lost their edge quite quickly. Thereafter performance was fine, but restarts were a bit theatrical. Douse the cylinder with fuel, fill tank &amp; then get it started. A sensible cylinder bore taper &amp; selecting a piston with lower expansion coefficient  lower than the cylinder would have fixed that.

Also worth mentioning is that these engines seem to have relatively poor suction. Our attempts at the time in using them as diesels on suction in combat models were not satisfactory.

The factory diesels have a fairly primitive diesel conversion setup that uses a cast iron insert and contra-piston. I doubt that one of these would come up to the performance figure that we obtained, but is probably not intended to do that and at more moderate speeds, it would be all smiles from the user.

Maris Dislers

RE: Why (an Enya 11 CX D) Diesel?
 

I recently bought a Enya Ultra 11CXDS model diesel engine. I hope to test it out later. I wonder what makes a Ultra 11 CXDS different from the other engines. Or is the Ultra 11CXD the same thing.

http://i248.photobucket.com/albums/g..._engine_02.jpg

http://i248.photobucket.com/albums/g..._engine_03.jpg

http://i248.photobucket.com/albums/g..._engine_04.jpg

http://i248.photobucket.com/albums/g..._engine_05.jpg

http://i248.photobucket.com/albums/g..._engine_01.jpg

RE: Why (an Enya 11 CX D) Diesel?
 

It is not II (as in two) but rather 11 as in .11 cubic inch.
I think the S simply stands for C/L rather than a throttle type. The Letters from Enya are a little odd, here is my take on the notations (only based on the engines I have);
S: C/L venturi
TV: throttle valved
TN: twin needle throttle valved
CX: AAC or ABC technology, on the .11 the Ultra means that it is ABC and 2.1cc compared to 1.8cc and AAC for the non-Ultra ones
SS: twin ball bearings
BB: single ball bearing

Interesting information from MarisD. I have noticed that there is no pinch on the AAC engines, even when straight out of the box, and now I understand why...

RE: Why (an Enya 11 CX D) Diesel?
 

Sorry, 'SS' doesn't mean twin BB. Some are plain bearing, some single ballraced, and some twin. I think it means 'Super Sport', but stand to be corrected.

Steve

RE: Why (an Enya 11 CX D) Diesel?
 

Hi Steve, 'SS' could well mean 'Scavenging Schnuerle' (from their own cataloging system) as opposed to 'Scavenging Cross flow' but they all seem to have the two piece split casting that is so typical of Enya's designs.Cheers.

RE: Why (an Enya 11 CX D) Diesel?
 

Nah, looks like I was actually right for once: http://www.supercoolprops.com/articles/enyasdzwolak.php

RE: Why (an Enya 11 CX D) Diesel?
 

Thanks guys, it was weird, i was thinking 11 but wound up typing in II instead. But on my monitor it is tough to tell the different between a 11 and a II. I went ahead and corrected my earlier post.

RE: Why (an Enya 11 CX D) Diesel?
 

Ok, in the spirit of corrections here is an updated list of acronyms (might not be fully correct yet):

S: C/L venturi
TV: throttle valved
TN: twin needle throttle valved
CX: AAC or ABC technology, on the .11 the Ultra means that it is ABC and 2.1cc compared to 1.8cc and AAC for the non-Ultra ones
SS: Super sport (all are schnuerle ported?)
BB: single or double ball bearing