MVVS 58 AND three blade
05-17-2006, 09:33 AM
#2
Senior Member
RE: MVVS 58 AND three blade
Danilo,
The normal 2-blade prop size for this engine is a 24x10.
A 3-blade prop that would have a similar power absorption and will spin at a very similar RPM is a 23x8.
A 3-blade 22x10 will be a bit heavier (~200 RPM less).
The normal 2-blade prop size for this engine is a 24x10.
A 3-blade prop that would have a similar power absorption and will spin at a very similar RPM is a 23x8.
A 3-blade 22x10 will be a bit heavier (~200 RPM less).
05-17-2006, 09:43 AM
#3
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RE: MVVS 58 AND three blade
Ok.
May be I'll install 22x10 3 blade.
The plane is QQ Yak 85 ". I think 23x10 3 blade is too much for this plane.
Do you agree with me?
May be I'll install 22x10 3 blade.
The plane is QQ Yak 85 ". I think 23x10 3 blade is too much for this plane.
Do you agree with me?
05-17-2006, 10:06 AM
#4
Senior Member
RE: MVVS 58 AND three blade
Danilo,
If you are using the MVVS #3204 canister silencer, this engine is capable of ~7,000 RPM on the 2B 24x10 prop size.
I cannot be sure you would not be better off with the lower 8" pitch and the larger diameter of 23" in 3-blades.
Since this engine can also spin a 26x10 2-blade prop, at 6,000 RPM, a 23x10 3-blade prop will be significantly lighter and well within the capacity of this engine, at a lower RPM level than a 22x10 3-blade.
If you are using the MVVS #3204 canister silencer, this engine is capable of ~7,000 RPM on the 2B 24x10 prop size.
I cannot be sure you would not be better off with the lower 8" pitch and the larger diameter of 23" in 3-blades.
Since this engine can also spin a 26x10 2-blade prop, at 6,000 RPM, a 23x10 3-blade prop will be significantly lighter and well within the capacity of this engine, at a lower RPM level than a 22x10 3-blade.
05-18-2006, 01:02 AM
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RE: MVVS 58 AND three blade
I have already a mvvs 58 Engine installed on extra 330 2,3 mt wingspan.
Sometimes, start backward. Can you explain why?
Thanks
Danilo
Sometimes, start backward. Can you explain why?
Thanks
Danilo
05-18-2006, 02:33 AM
#9
Senior Member
RE: MVVS 58 AND three blade
Danilo,
The cylinder porting and the reed-valve induction, work equally well both ways...
The ignition may be a tiny bit over-advanced, but this should be overcome with a more brisk flip of the prop, at startup.
The cylinder porting and the reed-valve induction, work equally well both ways...
The ignition may be a tiny bit over-advanced, but this should be overcome with a more brisk flip of the prop, at startup.
05-18-2006, 05:06 AM
#10
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RE: MVVS 58 AND three blade
Plaese I have another question.
If my engine runs at 7100 RPM playing carbon fiber 2 blade 23X10...how many hp is the power?
If my engine runs at 7000 RPM playing carbon fiber 3 blade 22X10...how many hp is the power?
Thanks
If my engine runs at 7100 RPM playing carbon fiber 2 blade 23X10...how many hp is the power?
If my engine runs at 7000 RPM playing carbon fiber 3 blade 22X10...how many hp is the power?
Thanks
05-18-2006, 07:13 AM
#11
Senior Member
RE: MVVS 58 AND three blade
Danilo,
You can go to Pe Reivers' home page at: http://home.wanadoo.nl/pereivers/Goodies.html .
From there you can either down-load the PropPower calculator (if you have a spread-sheet program, like MS Excel), or you can operate it on-line from the web page.
You must first enter your propeller constant (cell L8) and then use the model from RPM, diameter and HP numbers, to find what you want to know.
The material from which your prop is made is not enough to determine the prop constant, but several popular brands are listed.
Pe would, I hope, add Bolly Clubman, Bolly Wood, different Master Airscrew props and the generic numbers seem too large for narrow blade carbon fibre 3 and 4-blade props....
You can go to Pe Reivers' home page at: http://home.wanadoo.nl/pereivers/Goodies.html .
From there you can either down-load the PropPower calculator (if you have a spread-sheet program, like MS Excel), or you can operate it on-line from the web page.
You must first enter your propeller constant (cell L8) and then use the model from RPM, diameter and HP numbers, to find what you want to know.
The material from which your prop is made is not enough to determine the prop constant, but several popular brands are listed.
Pe would, I hope, add Bolly Clubman, Bolly Wood, different Master Airscrew props and the generic numbers seem too large for narrow blade carbon fibre 3 and 4-blade props....
05-18-2006, 09:28 AM
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RE: MVVS 58 AND three blade
Dear Dar:
You wrote "The cylinder porting and the reed-valve induction, work equally well both ways... " but in the instructions I got (ver 1.5) I can see the next note in red "If the engine starts to run backwards do not open the throttle - stop the engine immediately! Otherwise the engine can be damaged!" in the Carburator Adjustment section ... Have I understod somthing wrongly?
Thanks in advance,
Javier - Madrid
You wrote "The cylinder porting and the reed-valve induction, work equally well both ways... " but in the instructions I got (ver 1.5) I can see the next note in red "If the engine starts to run backwards do not open the throttle - stop the engine immediately! Otherwise the engine can be damaged!" in the Carburator Adjustment section ... Have I understod somthing wrongly?
Thanks in advance,
Javier - Madrid
