THE NEW MT 57CC ENGINE

[sinergy]

Sorry to hear that Rich.

Well it has taken me a bit of time to track this down... but just for comparision sake here are some numbers I dug up from 1.5 yrs ago.

This was done with just an engine on a bench with a pretty good scale.

Personally thrust numbers don't mean much too me.. there is too much opportunity for variation in calibration, geomatry, etc.. Atleast with a tach and popular prop I know a ballpark of how the engine performs.

Anyhow.. you guys can compare the rpm / prop to the scale readings to see if it helps narrow down some numbers.

NX 24x8 6400 rpm 33lbs of thrust
Xoar 23x8 7100rpm 34lbs 2oz of thrust
Xoar 22x10 7200rpm 30lbs of thrust
Mejzlik 22x8 7450rpm 30lbs 14oz of thrust
Xoar 22x8 7550rpm 32lbs 10oz of thrust

[hughes500e]

OK guys, I received my MT57 today. I carefully peeled the tape off to find out it was double boxed. Once I opened the factory box there was a nice manual, packing list and a muffler in a tray along with 3 bags of goodies wrapped in thin foam. I removed the upper tray with the muffler attached and there she was, mounted to another cardboard tray with pull ties, impressive. I removed her from the cardboard trays and laid her out on the table. The first thing I said, nice machining, look at that! The second thing I said, it's small. The carb came unmounted and I have to be honest, I looked at the reeds and said, pretty thin, I gently pushed on them and one is not seating, I will be turning it around or changing them; they are made of mylar! I also got an NGK plug. I am extremely impressed so far, very nice looking engine!

Here are a few pics.......

[GhostRider32]

I asked Larry but have once again forgotten, which NGK plug is the replacement when I need one? Thanks.

[mistydee0]

	Quote: Originally Posted by GhostRider32
	I asked Larry but have once again forgotten, which NGK plug is the replacement when I need one? Thanks.

Hi Ghost Rider,
If you have the 3/4"hex you need a NGK 6A plug. to fit the cap.

Larry LS PRO ENGINES

[hughes500e]

The NGK plug I have received with my engine: NGK-BPMR6A

[Al Lewis]

Nice looking engine. What plane you going to put it in???

[hughes500e]

She'll be going into a scratch built modified Goldberg Sukhoi SU26MX. The original plans were enlarged 12%. It is now an 83" 15 Lb monster. If I get 26 to 30 Lbs of thrust from the 57, the modified Sukhoi should be a blast.

[Al Lewis]

Sounds like just the ticket!! SHould be an awesome combo.

[soarrich]

I didn't get the 33 pound thrust video today. I took the wrong header so we didn't get to duplicate the setup from a couple weeks ago, couldn't even use it on the plane or test stand. I tried just using the stock muffler, only 28 pounds of thrust, about 6800~6850 rpm. I figured well I'll give no muffler a try to see what the muffler cost in rpm, I was shocked to find the stock muffler actually gains 200 rpm over open exhaust! This motor is exhaust sensitive, I thought the header I had on it when I did the test was about like a stock exhaust, now I'd say it was good for at least 500~700 rpm gain. I looks like a good exhaust set-up will really pay dividends. I try again with the correct set-up when I get back Monday.

[Al Lewis]

Most engines require some degree of back pressure to operate at their full. Two-strokes are particularly sensitive to this. When you get it exactly right the pulse of the exhaust back pressure will push any raw gas mixture back into the cylinder so you're not pumping out raw fuel and you're not trying to burn exhaust gas.

[RTK]

Yep, they also tend to go a little lean.

[GhostRider32]

Hi all,

I test ran the MT57 today and it ran really well. It is my first gasser so I really don't have any personal experience until today but I can tell you that I am happy with the engine.

It took me a few flips to get it started since I really didn't know what I was doing and I actually called Larry and he walked me right through the first time start procedure. Once the engine started, it idled very low and transitioned perfectly. Restarts were very easy. There was no lag between idle to full throttle, just a smooth (fast) rpm increase the whole way.

I was using the short throttle arm and asked Larry what people were using for the throttle arm extension but I need to be reminded, what do I need to buy to put on the throttle arm to hook the servo to? Thanks for the help.