rc bugman

My Feedback: (30)

Choosing an engine is difficult without information independent from the engine manufacturer/dealer network. Different criteria are often used in claims to garner or protect the market share. Collectively, we modelers have the hard data to help each other with the data necessary to evaluate available engines before purchase. The top end engine competition appears to be between RCS/ZDZ and 3W. Help me build this database for our own collective use. While engine rpm varies with propeller, atmospheric conditions etc., this measurement can be contributed by most of us and the range of performance can be listed as a range. This information is a better indicator of flight performance than listed HP or calculated thrust. This basic information can then be used by individuals as they wish.

Please evaluate the data listed on the table and help me correct the information listed below. In addition, please send me (email) engine performance data and I will add it to the table.


Single Cylinder engines

Engine . . . . . . . . . . . .Wt.(lbs) . . . . . . Hp . . . . . . . . . . RPMs/prop

RCS 140 . . . . . . . . . . . . 2.0 . . . . . . . . 2.9 . . . . . . . . .18x8 MAS; 7200
(22 cc)

3w-24 . . . . . . . . . . . . . .2.65 . . . . . . . .2.5 . . . . . . . . . 18x8 MAS; 8000
. . . . . . . . . . . . . . . . . . . . . . . . . . . . ? . . . . . . . . . . . .18x10 MAS; 7200
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18x10 APC; 6900

RCS 180 . . . . . . . . . . . 3.25. . .. . . . . . 4.0 . . . . . . . . . 18x8 Zing; 7800
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18x8MASS; 8000


ZDZ-40 (rotary valve) .3.15 . . . . . .. . .4.8 . . . . . . . . . .20x10 Mz; 7400
. . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . 20x10 Mjz; 7600
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20x10 MASS;7000

3W-42 . . . . . . . . . . . . . 3.97 . . . . . . . . 4.0 . . . . . . . . . 20x10 MAS; 7400

ZDZ-50 . . . . . . . . . . . . 3.37 . . . . . . . . 5.7 . . . . . . . . . .22x10 Mz; 7000

3W-50 . . . . . . . . . . . . . 4.36 . . . . . . . . 4.8 . . . . . . . . . .22x10 Dyt; 7500

ZDZ-60 . . . . . . . . . . . . 3.96 . . . . . . . . 6.5 . . . . . . . . . .22x10 Mz; 7300

3W-60 . . . . . . . . . . . . . 5.32. . . . . . . . .6.0

3W-70ius. . . . . . . . . . . 4.75 . . . . . . . . 6.5

3W-70 . . . . . . . . . . . . . 5.32 . . . . . . . . 6.5

3W-75ius . . . . . . . . . . . 4.75 . . . . . . . .7.5

3W-75 . . . . . . . . . . . . . .5.32 . . . . . . . .7.5

ZDZ-80 . . . . . . . . . . . . .4.29 . . . . . . . .8.5 . . . . . . . . . .26x10 Mz; 6500
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26x10 Mjz; 6700


Mz = Menz std; Mzu= Menz ultra; MAS = Master Airscrew Classic 4, MASS = Master Airscrew Scimitar, Dyt = Dynathrust. Mjz = Mejzlik, Zing = Zinger wood

Thanks Elson

hawkco66

No updates for you as I'm just now embarking on my quest for gas. But, in so doing I've been looking at ZDZ.

They sell two versions of the ZDZ40. Since the 4.8hp you've listed is the rotary valve version, I recommend you specifically mention (rotary valve) next to your RPM numbers for the ZDZ40.


Thanks,
and this is great information.

hawk

lenough

Great Idea.

FYI, Menz has a Standard Propeller and an Ultra Propeller.

Antique

My Feedback: (4)

www.rcfaq.com
thousands of prop/rpm combinations, all engines..

bn120

My Feedback: (1)

are all these weights bare no ignition or muffler?

Darin

rc bugman

My Feedback: (30)

rcign

I looked at the website and as you stated, there is a lot of information. However, I did not see a lot of information on 3W engines or ZDZ. These engines do not seem to get reviewed and the source of information is usually manufactures' data/claims. I would like to offer a database with a range of information from the end user. I am interested in measured data, not calculated data. I am also planning to expand the list to 3W and ZDZ twins.

bn120

As near as I can discern, these wts are the engine and ignition. If the wts are wrong, please let me know and I will change the value.

rcign

A lot of pilots use Zenoah engines but I am trying to keep this comparison of useful size between the 2 top-end engine manufactures.

Elson

Antique

My Feedback: (4)

Dumb question..What constitutes "Top end"...
Good way to start a war here , almost as good as "What is the best oil ?"
Have been repairing RC gassers for 15 years, almost everything out there...(Including many 3Ws)...Some look better on the outside, but inside they're pretty much the same..There were a few notable really bad exceptions, but they're no longer around....

dougnlynn

My Feedback: (1)

Good idea, love real information. I'm looking at using 2 RCS 140's on a new plane, and although I did not think they would be *the* highest power, you show a 3W-24 swinging an 18x8 MAS 800 rpm higher. Anything about the info that would help understand this? 800 rpm is a lot.

doug

Diablo-RCU

My Feedback: (1)

Say Elson:
To get good comparisons, you need to bolt some Menz and Mejzlik props on those 3W engines. You might also like the improvement for flying those planes.

kram-RCU

I'm only getting about 6,900 rpm out of the 3W24's swinging 18 X 10's. They ARE less than 20 flights old, but I don't think the RC Rport review got much more than I am. I love the engine, but your numbers seem a little high.

mt

Kris^

My Feedback: (1)

I have an RCS180 with the "Pitts" muffler. . out of the box it turned a 18-8 Zinger at 7700-7800 rpm. I switched to a 18-8 Master Airscrew "scimitar" series wood prop and picked some rpm, to 7900-8000 . Have not fully broken the motor in yet.

Antique

My Feedback: (4)

3W 24..18-8 prop..6900 rpm..18-6 prop..8400 rpm...
Amsoil 100-1, 7000 feet altitude, 40 degrees temp....
I will advance the timing to see if it gets any better.My first converted Zenoah G260PU turned the 18-6 at 9000 rpm..Is it "top -end" enough ? (Sorry, couldn't resist) Maybe there's room at the "top"
Update..Same engine, timing advanced, same rpm....
I should have some more 260s and a new Mejzlik prop today, more tests with a real prop.....

John Murdoch

My Feedback: (11)

Hey,
In trying to figure out what would be the best motor for me, I was doing some research on the ZDZ 50 vs. the ZDZ 60. RCShowcase http://www.rcshowcase.com/zdz60rv.htm shows the horsepower for the ZDZ 60 is 6.5. When I looked at the manufacuter's web page, http://zdz-modelmotor.cz/zdz/en/ they show the horsepower at 5.4. Be careful because some distributors show 6.5 and some show 5.4 hp. That's all that I need to determine the best bang for the buck. The ZDZ 50 is almost 3/4 of a pound lighter and has a quarter horsepower more.

Diablo-RCU

My Feedback: (1)

Since none of the gas engine manufacturers have a dynamometer (Zenoah might be an exception), HP figures are just poor guesses for marketing. As RCign pointed out, the only thing that counts is Prop size and brand and measured rpm. The engine that turns the same prop fastest, has the most power....that simple.

rc bugman

My Feedback: (30)

Sorry guys for the slow response. I have been on the road the past week. Work getting in the way and all.

I present the numbers as a starting point for you all to help me fill in the blanks with useful information. I will be updating the table with the information you provide.

3W-24 This is the engine that I have the most experience with. I use 15 of them in my university research project.

Diablo: The prop choice (18 x 8 MAS classic 4) was chosen when the set up was designed to fly the sampling plane between 42-45 mph at full throttle. Other props may work better but when landing a plane with wing loadings in the range of 40 oz/sq ft on unimproved runways complete with rocks, prop damage is a common reality. If others have data with other props, I will add it.

Kris: Thanks for the data. I will add it to the chart.

Kram: What brand of 18 x 10? The rpms listed were from a MAS classic 4


Keep the data coming!

Elson

kram-RCU

18 X 10's are APC's. Running at 1,200 feet elevation.

mt

kram-RCU

Sorry to sound dumb, but: What's an MAS classic 4 ? And who sells them?

mt

CGAV8R

My Feedback: (2)

MAS=Master Airscrew
Classic 4 is the model.

texasporty-RCU

What I would like to see in a database is the weight of each engine including the ignition, spark plug, and muffler (state weight and design muffler). I spend to much time trying to determine what different engine weights are.

rc bugman

My Feedback: (30)

Kram;

What kind of muffler are you using on the 3W-24. I get the best performance out of the pitts muffler.

Elson

kram-RCU

yep, Pitts style, from Cactus

mt