rmh

I will give it a try - my Sony is pretty good at close up.

captinjohn

Here is a experimental Homelite Glow inside.

Charley

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Captin,

Can you give us a pic of the ports in the sleeve?

TIA,

CR

rmh

That is the settup - the ports are open -

captinjohn

Charley: Here is a couple of different views of intake and exhaust ports. The other photo shows the sleeve and how the ports are formed. Not much sleeve in bypass aera. Less friction too. I was really suprized myself, when I first seen how it was done. Just think, in boats these rev twice as high as in an airplane. Thanks Captinjohn

captinjohn

photo no 3 last one

Charley

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Thanks, Captin,

Holy smoke! There sure isn't much support for the ring when the ports are open, is there? I thought there was a sleeve that you had removed to better show the pasages.

I had a Mac MC-6, in my Go-Karting days, that I added a boost passage straight up from the crankcase to. I had humongous tilted intake ports in the sleeve, no center rib in the exhaust port. The thing ran super until the thin ring snagged in the exhaust port. Wasn't much usable left. (G)

CR

rmh

Charley - the new ZDZ engines switched from huge ribbed exhaust ports to huge oval downward facing exhaust . I also wondered about unsupported ring - but so far so good .
The multiple open intake ports also were a bit surprising -but having run the hell out of em - no problem.
When we first worked with the chain saw stuff - the porting was -well -much more conservative.
It looks like the boys -at least some of the boys, have got this formula working well -
I ran dual Mac 10's on my Moss Cart - about 40 years ago !

OUTCAST

You always surprise me Dick, I ran Mac 91A's and Westbend 820's. You know we're showing our age. :^)

pe reivers

Directional porting is a must-have for best power, though the name is a bit misleading. It means, that all four walls of the port duct are shaped to accomodate the gas flow to it's best properties and directional flow stability. Normally, that should be slightly narrowing towards the cilinder port. It also allows for better flow turbulence control, which is important to low end torque and a wide power band.
I doubt however that the engine will, or will need to, acquire 80cc performance. You can only get that by raising rpm, and that is not always possible because of noise limitations, and would limit the market niche too much.
Having said that, the engine seems an exciting project for speed tuning, since most limitations to the high end power have been removed using this particular porting design. It is quite easy to produce a rear cover with a rear rotary valve, using a simple lathe, for those willing to experiment. Well designed reeds however, will hold their own, as proven by motoX engines. These large aircraft engines never run beyond 10000 rpm because of supersonic prop tip speeds. This is typical reed realm.
FWIW: The engine is expected to be ready in spring 2003.

captinjohn

pe reivers: Can you post some photos of that new engine?? Thanks Captinjohn

Diablo-RCU

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Hello Pe:
Will you be selling the new MVVS-58 gasser, or is it only being sold by the US distributor? Will they be using the Falkon ignition? Are they working on other larger engines too?

pe reivers

The prototype has been presented to Morris, and they took all the pictures that you will ever need.
last week, I contacted MVVS about availability, and they did not say that I could not get it when it was ready to market.
Judging the pictures, it looks like they will use their standard ignition on this engine.

bobi

any further news on this 58cc engine??

digitech

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dont forget any stupid comment about engine designing think about this:

most of the engines around came of industrial machines
mvvs designed ONLY aircraft engines
3W ONLY uses reed valve,s
why are they bad?
i did also carting ,dont forget! reeds go broken when they suck in lots of debree that is it!
and also your cart problably had a 100 cc engine that makes about 18000 rpm,s that will also shorten their life

you use a good oil like castrol tts you will have no worries
dont you think these guys now what they are doing??
i have 2 of these mvvs engines
i have one gas engine 35cc prop 20x10
weights 1800 gram,s

same performance with the same plane with a zenoah 62
i stopped fully with zenoah,s
they are at my opinion the engines 10 years ago
but now they are stuck in their own fortune
they cant even develope a new one
still use a crap magneto ignition , wich if not carefull brakes your fingers

try a mvvs or a 3w for a change 2 times the power for 2 times less weight
all start easy without scaring you to death

sorry about my english

reg Sandor

Forgues Research

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Or ZDZ for that matter. Purpose built engines from the ground up