gregziemba

whats so good about 4 stroke engines because they are twice as much as 2 stroke engines. I heard that they save fuel is that true? But what else?

Flying freak

yes the save fuel as they fire half the time as 2 strokes they have more torq so they like swining larg low pitch prop (3D) also the sound. can you imagine that perfict warbird that is completly scale only to hear a sreaming 2stroke [:@]

gregziemba

how much fuel do you think they save prepared to 2 stroke engine or is it not really noticeable because nitro is so epensive!

brooke

I have just started to use a four strokes this spring. I did so for the sound only. As for how much fuel they will save all I can really say at this point is that I took a two stroke out of the plane I put my four stroke in, the two stroke was a O.S.61FX and the new four stroke is the O.S.91. With the two stroke I could fly for 12 minutes and then land. Same plane and same fuel tank, but now with the four stroke I am able to fly 15minutes. If this will help any.

gregziemba

thats a little difference and thanks for the help. hey 3 min is 3 min

MinnFlyer

My Feedback: (4)

I rarely use 2-strokes anymore, but when I do, the three things I notice most are:

1) The crappy toy-like sound

2) higher fuel consumption

3) the God-awful slimy mess they leave all over the airplane!

Once you go 4-stroke, you'll never go back - unless you LIKE that slimey mess

Now before the 2-stroke guys jump all over me, i will admit that 2-strokes have their place. That place is not in any of MY airplanes if I can help it.

js3

My Feedback: (3)

Sorry, but even a four cycle sounds ridiculous on a "perfict" (sic) warbird. Not much a modeler can do to duplicate the authentic warbird's engine roar.

MinnFlyer

My Feedback: (4)

Maybe not, but a 4-stroke sounds much less embarrassing

Besides, we can't all afford one of these for our 1/4 scale Mustangs and Spitfires:

[link=http://dynamotive.netfirms.com/merlin/]1/4 Scale Merlin[/link]

js3

My Feedback: (3)

Mamma always said "If something's worth doin, it's worth doin' right."

Yeah, I can't afford that either but a guy can dream.

Back to the topic... Fuel consumption shouldn't be a consideration in my opinion. I've run both two and four cycles and the cost of fuel didn't cross my mind.

Yeah, four strokes have their place. It's nice to turn a bigger prop if you want to. Some people like the sound better. Some people mistakenly state that they are quieter.

But if you want to go fast, nothing but a two cycle will do.

Insanemoondoggie

MinnFlyer your making me drool ! 20 or so years ago we had a few of these full scale , stuck back , hidden in the corner of the hanger.

Insanemoondoggie

[link=http://www.rcuniverse.com/magazine/newproduct.cfm?product_id=1835]Sound[/link] Here ya go. problem solved lol All I did was skake my head.
[/quote]

Sorry, but even a four cycle sounds ridiculous on a "perfict" (sic) warbird. Not much a modeler can do to duplicate the authentic warbird's engine roar.

[/quote]

js3

My Feedback: (3)

Yeah, yeah, I know. Have you seen this installed on any plane? I have a hard time believing this won't sound ridiculous too.

Insanemoondoggie

No I have`nt seen anything but the video. I`m sticking with my 4 strokes.

da Rock

Yeah, hearing a scale P-51 or Spitfire fly by with it's single cylinder 4-stroke singing out a perfect duplication of the sound of a 1,500HP, Rolls-Royce or Packard, 12 cylinder, Merlin really is...... really is...... really is NOT WHAT HAPPENS.

An overweight, underpowered, overpriced single cylinder doesn't sound any more like a Merlin than the lighter, more powerful, and more affordable type single cylinders. Not by any stretch of the truth or imagination.

How are 2cycles different from 4 strokes?
They are lighter.
They are measurably more powerful.
They are appreciably less expensive.
They are often easier to operate.

As for how the two sound? Beauty is in the eye of the beholder...... or in this case, between their ears. We recently asked a couple of visitors to the field to pick out the "best sounding" model. They all picked out the one airplane that had a gasoline engine in it. It was a 2cycle gasoline engine. You want an engine that runs clean? Get gas. Want an engine that uses less fuel? Get gas. Want an engine that sounds different? Get the ones that turn the biggest props the slowest. Gas engines do that too.

You want to get the most power and performance for the best price? 2 stroke, glow fuel....................

MinnFlyer

My Feedback: (4)

No mistake about it. The latest version of the 91 surpass REQUIRES muffler pressure. But before that, I usually ran my 91's without any muffler at all - just a straight pipe. And I still run two of my OS 70's that way

Oh, and BTW, nobody complains that they are too noisey

ChuckW

I have both 2-strokes and 4-strokes and I like them both. Regardless of which you personally prefer, there is one thing I have found to always be true: you get what you pay for. Buy a good quality engine from a reputable manufacturer and you'll have less frustration. I currently have two OS .46-AX 2-strokes. They are much easier to start and tune than some less expensive engines I have tried.

Heck, I never thought I woild say it but I even have an electric now on a little Yak-54 profile. It was odd ar first not hearing an engine but the little thing is a blast.

flipstart

The smaller 2 strokes do doubt have an annoying unscale like sound, the 4 strokes do sound some better. But put on a large 2 stroke like a OS 1.60 FX, with a pitts muffler and you get a nice rumble instead of that high rpm scream. On larger war birds the 2 stroke sounds much better. As for speed, the 2 stroke is king. Also with proper muffler placement, one can mostly eliminate the slim with 2 strokes and 4 strokes. 2 stroke or 4 stroke, they both sure are a lot of fun!!

js3

My Feedback: (3)

Ok, I'll concede the point if you're talking about muffled four cycle motors. That's just it though, most people don't muffle their four bangers. The most popular four cycle motors where I fly are YS 1.20s 1.40s etc. They are every bit as loud if not more so than the loudest (muffled) two cycle and to my ear, the sound is much more obnoxious with the YS than my Jett racing motors.

flipstart

I do have a 91 4 stroke on my L-19 Bird Dog with straight pipe and it sounds fairly realistic, not too loud, but then I like noise, who wants a quiet airplane, the real ones are very loud. Most 4 strokes with a muffler have a stopped up sound, kinda like a possum blowing thru a straw.

blw

My Feedback: (3)

I think one of the best sounding single cylinder 4 strokes is the Saito .56. It has a certain sound you can pick out from the others.

A 4 stroke Moki 5 cylinder sounds the best of all model engines that I've heard except for turbines. Nothing like hearing one of those either idling less than 900 RPMs or going full tilt.

Gringo Flyer

My Feedback: (18)

Fuel savings is a really a non factor. I really like 4 strokes personally. If money is tight 2 strokes are great but given the choice I will almost always choose a 4stroke. I have mostly 2 strokes but now I fly them less and less. If its speed Im looking for no doubt the 2 stroke is the choice. For 3d, sport, or scale flight 4 stroke is the way to go.

With the 4 stroke, I really like the sound and throttle response. Although my ST90 with a Jett muffler sounds pretty cool too.

MinnFlyer

My Feedback: (4)

Now there's a mental image that I hope won't be visiting me in my sleep [sm=what_smile.gif]

flipstart

Think about the possum for a while, minnflyer, it will put you right to sleep. Just don't dream too much.

Dave McDonald

My Feedback: (19)

For those who hate 4 strokes:
http://mypage.yhti.net/~dmcdnld/4cycle.htm

For those who hate 2 strokes:
http://mypage.yhti.net/~dmcdnld/2cycle.htm