THE NEW MT 57CC ENGINE

[Al Lewis]

	Quote: Originally Posted by closetguy
	well i got 45 minutes of run time on the 57 now,here's what i got. ES composite pipe 12" header that was made for a 58gx2,just moved the holes in a 1/16. pennzoil, 32-1 air cooled,87 octane 6800 on a 23-8 mejzlik 6700 on a bolly 23-8.this is about 100 rpm's off peak. engine runs good, i do half to say i got the china plug in it and have a small mid to high end miss, still need to get the rite plug.

Based on that I'd say either something is wrong with your setup or you just under-performed a DL-50.

[davemilw07]

I'm curious, why hasn't RCIGN given us a performance report yet ?????

[joe barrington]

I did tell u the Plugs are naff and best put in the bin.6700rpm isway to low on that prop.You should be achieving 7100 -7300 easily.I would agree that your set up or tuning is out of whack.Must admit that the hype surrounding the ES composites pipe,for me,is a bit overstated and i ended up selling it to some other unsuspecting Englishman.Personally i didnt like it at all,now using an MTW on 1 of the 88 Yaks and and a KS pipe on the other Yak

[krayzc]

joe what difference did u see in the swap out change?

[Al Lewis]

I would certainly hope that a 57cc would do better then spin a 23 X 8 at 71-7300 rpm. With the added displacement you would expect it to spin up a 24 X 8 or 10 to 7200. Somebody throw a Vess 23A on one and let's get a benchmark. My DL-50 currently is tuned to spin a Vess 23A at 7350 rpm on a stock muffler and Belray H1R at 40:1. Anyone out there got similar numbers from a DA or 3W we can use?

[soarrich]

23A Vess with a header I got 7400rpm and 33 pounds 8 ounces of thrust. The header is about the same as a stock muffler. Pennzoil at 32:1.

[closetguy]

i am going to remove the pipe and try the stock muffler.also going to check timing just to make sure.
also what spark plug are you guy's using?
you know i can lean out the top end a little but there is just not that many rev's left in it.
and as far as the low end i have had it so lean that it would not transition and so rich that it did nothing but burble.it may just be the plug, i tried a RDJ7Y plug but was to small.

[soarrich]

To quote Ralph.......
Go to your local auto supply...ANY 14mm thread spark plug will work, resistor or non...

[luckyflyer]

What prop drilling guide should I buy to drill props for the mt57.
Thanks,
luckyflyer

[closetguy]

well i found one problem,the timing was set at 14 degrees BTDC.and of corse i ran out of adjustment and had to drill and tap two lower holes to get it to 28-30 BTDC.so i will try again tomorrow and see if it made any difference. be nice if it was this simple of fix.

[forgues research]

	Quote: Originally Posted by closetguy
	well i found one problem,the timing was set at 14 degrees BTDC.and of corse i ran out of adjustment and had to drill and tap two lower holes to get it to 28-30 BTDC.so i will try again tomorrow and see if it made any difference. be nice if it was this simple of fix.

Doesn't this engine have an auto advanced ignition like all solid state?? If so, it was actually advanced too much , and you should retard closer to O degrees not more advanced.

Roger

[soarrich]

	Quote: Originally Posted by forgues research
	Doesn't this engine have an auto advanced ignition like all solid state??Roger

No, they are called auto advance, but they really auto retard.

This is what Pe found.

About the RCexcl ignition:

below 500 rpm, the ignition does not retard! So flip the prop slowly, and she will bite.

above 800 rpm, the ignition retards a full 21 degrees.

at 1500 rpm, the retardation is lessened up to ~3500, when retard is nil again.

A very nice range that allows excellent throttle response without any power jumps or surges.
up to 8500 rpm, the ignition fires as set by the pickup!
above 8500, there seemed to be a very slight retard again, catering for the higher squish velocities encountered in the combustion chamber.

[soarrich]

	Quote: Originally Posted by closetguy
	well i found one problem,the timing was set at 14 degrees BTDC.and of corse i ran out of adjustment and had to drill and tap two lower holes to get it to 28-30 BTDC.so i will try again tomorrow and see if it made any difference. be nice if it was this simple of fix.

I found that too, I just cut the slots longer, and I think used 3mm Allens to be able to get a few more degrees out of it. I think I mentioned it to Larry, so he could get Tomy Shen to fix it, I make sure Larry knows about it.

[mistydee0]

	Quote: Originally Posted by closetguy
	well i found one problem,the timing was set at 14 degrees BTDC.and of corse i ran out of adjustment and had to drill and tap two lower holes to get it to 28-30 BTDC.so i will try again tomorrow and see if it made any difference. be nice if it was this simple of fix.

Tom, The first thing I did when I got the engines was to put on a degree wheel and check timming. You are 100% right when you say it is at 14 degrees, as that is what I got. I called China and talked to Tomy about this. He said it was suppose to be at this, and the box would take care of the rest of the timming. {as per the R/C excel co. that makes the ign.} BUT!!! Soarich and I bumped the timming up higher and got more RPM out of the engine. I have been slotting the brackets on all the engines going out to increase the timming. So you are right. After the first few engines that went out I started to measure the distance from the edge of the Hall sensor to the edge of the triggering magnet and using the formuler of circ. and pi I measured every engine that went out. {it was easier to do that then installing the degree wheel on each engine. Ralph also told me the measurement should be .357 and that is what I got when the engine was at TDC.
So you are on the right track, tuning the engine. I do not think you really had to drill and tap new holes but that was one way to do it. Thanks for your imput, and you taking the time to properly tune the engine.

Larry, LS PRO ENGINES

AIRBORNE RANGER

[mistydee0]

Also, for everyone that is waiting for Ralph to post, be patient, he has sent the engine out to his test pilot for flight testing and videos. Also he is getting another engine from Tomy R/C in parts, to inspect measure assemble, and run tests. This is going to be done right. Plus Ralph has some issues with his better half in and out of the hospital, and running a business. Its not like he is getting PAID to do this review.

Larry LS PRO ENGINES



AIRBORNE RANGER