Real world engine comparisons
10-22-2006 | 06:53 AM
#26
My Feedback: (102)
RE: Real world engine comparisons
Dar, that 9,400 figure is probably right on, my old .46 MKII turns a Graupner 12x6 at about 9,000 but I preferred an 11x6 because with the 12x6 the midrange was very smoky, the HS needle could be set considerably leaner at higher rpm telling me that the airflow velocity (through the carb) was too low at full throttle at 9,000. The .53 has no issue like that.
10-22-2006 | 07:14 AM
#27
Senior Member
RE: Real world engine comparisons
Dave,
I was not doubting the RPM Wayne quoted; just his remark stating this Enya engine is particularly powerful.
I recall an engine review for the Enya .53 in MAN, some time in the '80, quoting RPM in the high 13Ks, on usable propellers...
...And all this without the super-charging of YS engines.
This .46 is making reasonable power for a normal four-stroke; not a commendably high power.
I was not doubting the RPM Wayne quoted; just his remark stating this Enya engine is particularly powerful.
I recall an engine review for the Enya .53 in MAN, some time in the '80, quoting RPM in the high 13Ks, on usable propellers...
...And all this without the super-charging of YS engines.
This .46 is making reasonable power for a normal four-stroke; not a commendably high power.
10-22-2006 | 07:38 AM
#29
Senior Member
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RE: Real world engine comparisons
ORIGINAL: Jaysbird
Artisan, I will try the 13-6 prop, but would I get the same effect by going up in pitch instead of diameter? (as a side note,I originally had a MA K-series 12-6 prop on it because it looks better but I could only get 9600 rpm out of it.
***Yes, going up in pitch would have the same effect. A 12x7 or 8 would be okay. If you are near 10k rpm, you are in the ballpark. Not to worry. Many four-strokes are not willing to rev real high, even with smaller than normal props. Where they shine is in swinging somewhat larger than normal props. If you have the clearance, the 13x6 would be really close to optimum because of the wider cowl that radial engined models tend to have.
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Another issue is because of the short nose of a Zero (and probably because its a cheap ARF) I had to add a whole pound of lead to the nose to get it to balance. AUW is 7lbs 8oz. At this point buying a bigger engine is not an option but I wanted to get an idea from some experienced 4strokers how this engine compares to others of similiar size and if it has enough omph to pull this weight.
***I would try to move the radio installation as far forward as possible in order to reduce the amount of ballast that is needed, if you haven't done so already.
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And finally maybe those of you who have several engines (2s &4s) might create a reference post with practical rpm figures of what your engines are capable of with different sized props. That way when a modeler like me with no experience with 4Ss will have a real world reference to compare the various engines that are available.
Thanks again!,
~Jay
Artisan, I will try the 13-6 prop, but would I get the same effect by going up in pitch instead of diameter? (as a side note,I originally had a MA K-series 12-6 prop on it because it looks better but I could only get 9600 rpm out of it.
***Yes, going up in pitch would have the same effect. A 12x7 or 8 would be okay. If you are near 10k rpm, you are in the ballpark. Not to worry. Many four-strokes are not willing to rev real high, even with smaller than normal props. Where they shine is in swinging somewhat larger than normal props. If you have the clearance, the 13x6 would be really close to optimum because of the wider cowl that radial engined models tend to have.
---------
Another issue is because of the short nose of a Zero (and probably because its a cheap ARF) I had to add a whole pound of lead to the nose to get it to balance. AUW is 7lbs 8oz. At this point buying a bigger engine is not an option but I wanted to get an idea from some experienced 4strokers how this engine compares to others of similiar size and if it has enough omph to pull this weight.
***I would try to move the radio installation as far forward as possible in order to reduce the amount of ballast that is needed, if you haven't done so already.
----------
And finally maybe those of you who have several engines (2s &4s) might create a reference post with practical rpm figures of what your engines are capable of with different sized props. That way when a modeler like me with no experience with 4Ss will have a real world reference to compare the various engines that are available.
Thanks again!,
~Jay
***I agree that a data base is useful. Have you looked at the Tach Readings forum on RCU?
Good luck in your ventures
10-22-2006 | 07:38 AM
#30
Senior Member
RE: Real world engine comparisons
Dave,
I will have to take your word for it... Until 10 days ago, I had not owned a four-stroke engine...
After playing with the Saito, I agree it is very easy to operate. I guess the Enya is just as easy and even runs well on 5% nitro.
About a year ago, I discussed the remarkable Enya .53 4C with John Mikesell.
I guess it should sound like a Briggs lawn-mower that lost its blade... imagine a single cylinder four-stroke doing nearly 14K...
I will have to take your word for it... Until 10 days ago, I had not owned a four-stroke engine...
After playing with the Saito, I agree it is very easy to operate. I guess the Enya is just as easy and even runs well on 5% nitro.
About a year ago, I discussed the remarkable Enya .53 4C with John Mikesell.
I guess it should sound like a Briggs lawn-mower that lost its blade... imagine a single cylinder four-stroke doing nearly 14K...
10-22-2006 | 03:14 PM
#31
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From: Tokoroa, , NEW ZEALAND
RE: Real world engine comparisons
ORIGINAL: DarZeelon
I will have to take your word for it... Until 10 days ago, I had not owned a four-stroke engine...
I will have to take your word for it... Until 10 days ago, I had not owned a four-stroke engine...
I've found that my 4-strokes are *far* less fussy or finicky than my 2-strokes. They're pretty much "set and forget", which is great if you prefer flying to tweaking needles.
They don't load up with fuel and die if your idle is a bit rich, they will run at obscenely rich needle settings without losing much power (they just belch a snot-load of smoke) and they produce gobbs of thrust for their displacement.
They also seem quite a bit more civlized, creating their thrust without a lot of screaming and wailing.
Some people say that they love the scale-like 4-stroke sound, but to be honest, a single-cylinder model 4-stroke engine doesn't sound much like "the real thing" at all -- it sounds more like a tractor. However, my P51 Mustang with TT91FS and no muffler sure sounds nice on a full-throttle fly-past at about 12,500 RPMs. I had to take the muffler off because it sounded way to quiet to be realistic with the stock one on.
10-22-2006 | 04:13 PM
#32
My Feedback: (102)
RE: Real world engine comparisons
Harry, I ordered an APC 15x8 for the Saito 1.25, it should be here by Thursday and I'll give you the numbers. I eased another 1.20 rpm out of it by re-setting the valve lash back to the Saito recommended .004. The exhaust had an intermittent lean sounding crackle to it, even when set too rich, I suspected the .002 valve setting was the culprit and I was correct.
10-22-2006 | 04:45 PM
#33
Senior Member
RE: Real world engine comparisons
Good stuff Hobbsy.
It should be an interesting performance reference. Several guys run that prop on their 1.20 sized models at our club. A typical four stroke 1.20 in our neck of the woods will see somewhere around 9000- 9200 using it.
It should be an interesting performance reference. Several guys run that prop on their 1.20 sized models at our club. A typical four stroke 1.20 in our neck of the woods will see somewhere around 9000- 9200 using it.
10-23-2006 | 12:48 AM
#34
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From: Paramount, CA
RE: Real world engine comparisons
***I would try to move the radio installation as far forward as possible in order to reduce the amount of ballast that is needed, if you haven't done so already.
***I agree that a data base is useful. Have you looked at the Tach Readings forum on RCU?
However, my P51 Mustang with TT91FS and no muffler sure sounds nice on a full-throttle fly-past at about 12,500 RPMs.
10-23-2006 | 01:09 AM
#35
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From: Paramount, CA
RE: Real world engine comparisons
Artisan, I just looked through the Tach Readings sub-forum, This is exactly what I was looking for regarding "real world engine comparisons. Thanks for the info.
Now if only there was a forum on how to use these forums............
Now if only there was a forum on how to use these forums............
10-23-2006 | 02:22 AM
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From: Tokoroa, , NEW ZEALAND
RE: Real world engine comparisons
ORIGINAL: Jaysbird
XJet, Will all 4S engines run well without tank pressure from a muffler? I really don't like the look of the muffler hanging out the side of my Zero and noise is not an issue where I fly.
XJet, Will all 4S engines run well without tank pressure from a muffler? I really don't like the look of the muffler hanging out the side of my Zero and noise is not an issue where I fly.
10-23-2006 | 12:45 PM
#37
RE: Real world engine comparisons
To get rid of the smoke try a cooler plug. The Fox Miricle plug is slightly cooler than the OS F and the K&B 4C plug is about the coldest four cycle plug I have found. Be sure to lean out the mixture when you change to a cooler plug. You should gain some power as well.
