Real world RPM

[pe reivers]

WrongwayRC, It does not sound like your published rpm are correct.

[WrongWayRC]

Which ones?

[soarrich]

MT62

After about 7 gallons, DA header, KS can. 68*, 30' ASL. I ran the engine up got 6990 rpm with the NX 23x8, then flew it for 10 minutes, landed then got 6800 on the heat soaked engine. I changed the prop and ran the engine up to max on the next prop all with in 1 minute, then kept repeating the prop changes at 1 minute intervals. One bolt props are sure easier to change than 6 bolters.

Vess 22A 7350 rpm Too loud.

TBM 22x8 6660 rpm
TBM 22x10 6060 rpm
TBM 23x8 6150 rpm

NX 22x8 6900 rpm
NX 23x8 6800 rpm
NX 24x8 5850 rpm

Xoar 23A 6500 rpm

[Super08]

I was playing with my MT62 as well...

Engine at 220 degrees. Air temp around 70 and humidity at 94%.

22x8 Xoar 7100 (PJD)
22x10 Xoar 6660 (carbon)
23x8 Xoar 6600 (PJM)
These results were with the TomyRC twin stack muffler. I am going back out in an hour and I will try the 22x10 again with the MT57 muffler to see if there is any change.

[rcign]

Hey Rich, 44 looks great, But..
My very good Grish Brothers thrust chart shows 32 lbs for 22-8 @ 8000, 45 lbs for 22-8 @ 9000..
Interpolating shows about 38...Still VERY good, definitely not underpowered

[octanehuffer]

	Quote: Originally Posted by soarrich
	MT62 After about 7 gallons, DA header, KS can. 68*, 30' ASL. I ran the engine up got 6990 rpm with the NX 23x8, then flew it for 10 minutes, landed then got 6800 on the heat soaked engine. I changed the prop and ran the engine up to max on the next prop all with in 1 minute, then kept repeating the prop changes at 1 minute intervals. One bolt props are sure easier to change than 6 bolters. Vess 22A 7350 rpm Too loud. TBM 22x8 6660 rpm TBM 22x10 6060 rpm TBM 23x8 6150 rpm NX 22x8 6900 rpm NX 23x8 6800 rpm NX 24x8 5850 rpm Xoar 23A 6500 rpm

Did they forget to install the piston ring? Those numbers are the same I am getting on an Evolution 45. Vess 22b to 6930. I hope there is nothing wrong with it.

[soarrich]

	Quote: Originally Posted by octanehuffer
	Did they forget to install the piston ring? Those numbers are the same I am getting on an Evolution 45. Vess 22b to 6930. I hope there is nothing wrong with it.

I don't think there is anything wrong with the engine, it constantly turns better rpms on the same prop as my friends DA 50, which it should with 20% more cubes, but it weighs the same as the DA.

The E45 with a V22b @ 6930 and a MT62 with a V22a @7350 I'm not sure how to compare them. For me I look at the weight of the engine to the prop it can turn quietly, the V22a is a none starter for me, it's just to loud. I'm pretty sure I'm losing rpms to the canister, but I'm not going to install it, run it, shorten the header, reinstall it, it's not worth it to me. The setup I have has great throttle response, very good power, and is very quite, that works for me.

[Super08]

Rich I got the same numbers today with the MT 57 grey muffler and them again with the twin stack one. I tired the chrome one and lost rpm....

BTW I only have about 60 ounces of fuel through it so far.

[zoomer260]

	Quote: Originally Posted by soarrich
	I don't think there is anything wrong with the engine, it constantly turns better rpms on the same prop as my friends DA 50, which it should with 20% more cubes, but it weighs the same as the DA. The E45 with a V22b @ 6930 and a MT62 with a V22a @7350 I'm not sure how to compare them. For me I look at the weight of the engine to the prop it can turn quietly, the V22a is a none starter for me, it's just to loud. I'm pretty sure I'm losing rpms to the canister, but I'm not going to install it, run it, shorten the header, reinstall it, it's not worth it to me. The setup I have has great throttle response, very good power, and is very quite, that works for me.

My DL50 turns the Vess 22B faster than it does the Vess 23A. I understand Al got the same numbers with both on his early model. All I can remember now is I got 7400 whit the 22B and less with the 23A. I think it was 7250-7300.

[soarrich]

	Quote: Originally Posted by Super08
	Rich I got the same numbers today with the MT 57 grey muffler and them again with the twin stack one. I tired the chrome one and lost rpm.... BTW I only have about 60 ounces of fuel through it so far.

The chrome muffler was the replacement for the gray single stack muffler, it was a longevity issue, not power. My gray single stack lasted about 20 minutes before the stack blew off, I never asked for the replacement because I try to always use a canister.

Once you time it right and get a good carb rotator block the 62 is the best engine in the MT line.

[octanehuffer]

	Quote: Originally Posted by soarrich
	I don't think there is anything wrong with the engine, it constantly turns better rpms on the same prop as my friends DA 50, which it should with 20% more cubes, but it weighs the same as the DA. The E45 with a V22b @ 6930 and a MT62 with a V22a @7350 I'm not sure how to compare them. For me I look at the weight of the engine to the prop it can turn quietly, the V22a is a none starter for me, it's just to loud. I'm pretty sure I'm losing rpms to the canister, but I'm not going to install it, run it, shorten the header, reinstall it, it's not worth it to me. The setup I have has great throttle response, very good power, and is very quite, that works for me.

Yeah, just based on the props you tested, I am getting the same with the "E45". The 22A was spinning to 7300. Same as your MT62. Bigger must not always be better in the case of the MT62. What RPM's will it run with a pitts muffler?

[soarrich]

I don't have a pitts muffler, sorry.

[6443jb]

bme 116 extreme
jtec mufflers
27/10 xoar pt prop
40-1 oil belray mc-1
now 5gallons through it
80 degrees outside
temp on motor 220-230
6900rpms just keeps getting stronger

[Alexzzz]

3W157Xi, MTW RE3 tuned pipes, Mejzlik 32*10 2-blade; 6100rpm

[WrongWayRC]

I played with the new Rcexl tachometer just now. It plugs into your hall sensor with a Y and is just a reader, no memory or peak stuff. No battery, just the Y. I used an extension to bring the unit back to the cockpit area. Seems to be well built.

Very visible in broad daylight as you can see in picture. After I put tinted canopy on it was still easy to read. Shown here is an idle of 1,720 rpm. Operates from 3.5 to 8.4 v, is 41x17x12mm in dimensions and weighs 8.5 grams.


I tried to video it but the led's cycle too fast and it don't look right. Rock solid with the naked eye though. Just stocked a bunch on the shelf. Might make a new meaning to taking RPM readings.

Rcexl says it is accurate for their ignitions and wont guarantee others. Would love to find one of you guys with an eagletree and DA to do some testing and verify if it can be accurate on DA as well.