That's a nice pair of jugs!

[in2deep]

Just arrived today. I'll get one installed in the Whiplash tonight and start breaking her in tomorrow.

This is a continuation of this thread I started: https://www.helifreak.com/showthread.php?t=689924

Glad to have this project moving forward again. Hope to have good news to report soon.

[fastflyer20]

Nice Jugs!

[in2deep]

Looks like another TRM gem!

Fired up the first time I spun her over. Started with the low at 1-1/2 and the high at 1-3/4. Had to lean the low a 16th of a turn to get her to idle through the second tank. Kept the rpms around 4100 for both tanks on the ground. Really looking forward to getting these first 3 gallons out of the way.

For those of you monitoring temps, where are you placing your temp sensor, and what range of temps are you seeing?

(only for the purposes of data logging, I'm not tuning by temp)

[sargentfly]

I run my temp sensor under the spark plug. It runs around 220 after a good 10 minute sport flight add a few degrees for mild 3D.

[Sowa]

Originally Posted by sargentfly

I run my temp sensor under the spark plug. It runs around 220 after a good 10 minute sport flight add a few degrees for mild 3D.

That seems really cold for an under the spark plug temp.

Underneath the 3rd fin from the top, same side as the intake port, ~260-280F

[fastflyer20]

That is why unfortunately temp is not a good for comparison between different engines, different measuring methods and different setups. It is only relative to that Heli and the difference in 20 deg can be from running great to seized.

[rbort]

Sargentfly could be measuring the head with an IR head just after landing, in that case his readings would be OK.

-=>Raja.

[in2deep]

Temps climb quickly after landing. You can see here how quickly she heat soaks an additional 25* after shutting down.

[LoveToFly1]

i have seen temps as high as 380 with the specktrum sensor wrapped around the head. with a tuned pipe of course, turning 15,400rpm.

i later found that the sensor may have been off by 50 degrees or so too though, so i really dont know.

tune by plug and sound, and thats all you need.

[learnedthehardway]

Lmao!! Now that's an attention grabbing title, i bet this thread gets alot of views.

[in2deep]

Originally Posted by in2deep

(only for the purposes of data logging, I'm not tuning by temp)

Originally Posted by LoveToFly1

tune by plug and sound, and thats all you need.

lol, yup

I always test the Spektrum sensors before installing them in order to calibrate. To my surprise the ones I've used were all very close to the thermometer I was measuring against.

[DONVS]

I typically run 340F in Iu1 with a TRM270 and QD pipe in a whiplash turning 1900 rpm. This engine has over 20 gal of fuel through it at this temp. The sensor is within 2 % from 50 through 300 degrees C. This is using a Jeti sensor wrapped around the head with the sensing part one final away from the exhaust port and on the same side as the exhaust port. I have checked about 60 times and see zero increase after shut down. I also have never seen an increase on any full scale airplane after shut down. The fins may get hotter because of lack of air movement, but with the fire out there is no source of heat to the cylinders. Probably a measuring error, ie hitting a final instead of the cylinder wall. Don

[in2deep]

Interesting. This may be a matter of semantics, were probably talking about the same thing.

I've been data logging every heli engine I've ever owned (nitro and gas) and there has always been a period of temp increase after shutdown and before the temp begins trending toward ambient. True that the fire (combustion) is out, but so is the cooling process since the fan is no longer turning. Same principle as an intercooler in a forced induction vehicle.

[in2deep]

Back to the vx300:

Hovered a bit in the backyard today and I'm stunned at how smooth this thing is, even that its only on the 3rd tank. Tail was rock solid, even pig rich with a max rpm of 1388.

Cant wait to get this thing broken in. Its going to be a long few gallons...

[DONVS]

Originally Posted by in2deep

Interesting. This may be a matter of semantics, were probably talking about the same thing.

I've been data logging every heli engine I've ever owned (nitro and gas) and there has always been a period of temp increase after shutdown and before the temp begins trending toward ambient. True that the fire (combustion) is out, but so is the cooling process since the fan is no longer turning. Same principle as an intercooler in a forced induction vehicle.

Yeah we are saying the same thing. The temp increase that the thermocouple reports is the fins and the air around them, not the actual cylinder temp. IR guns do not give accurate results when aimed at aluminum. Thermacouples as used in RC have very small contact with the cylinder and once the fan stops and the air around the fins heats up that is the primary source of the heat that people call heat soak. The actual cylinder temp starts to cool imeadiatly after the fire goes out. PM me if you want the science involved.

[sargentfly]

Here is the link for the temp sensor i use. Both my whiplash gasser and Gas Goblin use them. The thermocoupler ring is about 2mm in diameter larger than the base of the spark plug. I remove the crush washer from the spark plug and place the couple ring between cylinder head and spark plug.





www.trailtech.net/digital-gauges/tto

[T-bone-1]

If is getting hot when it is shut off just keep flying it!!! Lol sorry buddy

[Sowa]

Originally Posted by sargentfly

Here is the link for the temp sensor i use. Both my whiplash gasser and Gas Goblin use them. The thermocoupler ring is about 2mm in diameter larger than the base of the spark plug. I remove the crush washer from the spark plug and place the couple ring between cylinder head and spark plug.





www.trailtech.net/digital-gauges/tto

I've used the trail tech stuff before on a motorcycle build and an FSAE car. Always had funky temp and rpm readings on their dashboard display. I'm probably biased with their products but the sensor itself may have not been the culprit.

[in2deep]

Originally Posted by T-bone-1

If is getting hot when it is shut off just keep flying it!!! Lol sorry buddy

You've got some wrenching to do my friend!

[in2deep]

Whip Gas - TRM vx300tt - ShankTech QuickDraw