R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro On-Road > Onroad Nitro Engine Zone

Reply
 
Thread Tools Search this Thread
Old 03-14-2007, 05:01 PM   #1
Tech Addict
 
Join Date: Jan 2007
Posts: 660
Default Engine temp range

Yes the ever asked question of "what temp should my engine be?"

now I know the answer is "tune to performance not temp."

However, what is the temp that no matter what is too hot? With my current engine which is a JP Modified Mugen x12, what temperature should I stay below? Looking for more concrete info other than "if it sounds and feels good then it's good." basically after running a few passes at high speed and bringing the car in I get temps around 260F and wanna know if this is safe. I can richen up a bit to drop temps right?

Thanks for any replies.
__________________
Kyosho V-One RRR - JP Modified Mugen X12 - GQ Racing Tires - Futaba servos - KO Helios w/Spektrum Pro - Maxy's Fuel
Losi 8ight 2.0 RTR for fun times
Dredd is offline   Reply With Quote
Old 03-14-2007, 05:21 PM   #2
Tech Addict
 
Join Date: Feb 2007
Posts: 511
Trader Rating: 1 (100%+)
Default

250 is a nice place to be at, i would say keep it within 10 degrees of 250 and you should be just fine.
randay is offline   Reply With Quote
Old 03-14-2007, 05:27 PM   #3
Tech Elite
 
rmdhawaii's Avatar
 
Join Date: Feb 2006
Posts: 3,804
Trader Rating: 4 (100%+)
Default

I agree with randay. As long as the engine is running well, I try to make sure it's in the 240-260F range. Less than 240 and I would say I'm running too rich. More than 260 and it should begin to sound too lean. 300+ is bad, although the CRF can handle 300+ without blowing up on you or burning plugs in 4-5 minute heats.

BTW ... I am by no means advocating running a CRF at 300+ degrees.
__________________
Nitro Knowledge Base: http://nitrokb.netne.net
My YouTube Channel: http://www.youtube.com/nitrokb -> Lots of on-road nitro & eletric action + some off-road as well
My Flickr Photostream: http://www.flickr.com/photos/nitrokb/
Kyosho V-ONE RRR WC (x2) \ XRAY T2'007 \ Also owned: XRAY NT1 & Mugen MTX-4

Last edited by rmdhawaii; 03-14-2007 at 05:38 PM.
rmdhawaii is offline   Reply With Quote
Old 03-14-2007, 08:48 PM   #4
Tech Addict
 
Join Date: Jan 2007
Posts: 660
Default

Ok then I will richen it up a little bit and make sure it stays below the 260 mark.
__________________
Kyosho V-One RRR - JP Modified Mugen X12 - GQ Racing Tires - Futaba servos - KO Helios w/Spektrum Pro - Maxy's Fuel
Losi 8ight 2.0 RTR for fun times
Dredd is offline   Reply With Quote
Old 03-15-2007, 04:50 AM   #5
Tech Master
 
choisan's Avatar
 
Join Date: Jul 2004
Location: San Francisco Bay Area
Posts: 1,236
Default

someone does it like this;
use thrumb to stop the engine at idel at flywheel, let it cold down, take out the plug, stamp the plug onto our hand or palm, you will see a ring by the fuel. The more wet it is, then it tells you there is still room to lean.
But make sure you observe the temp and having enough smoke.
just my 2 cents
choisan is offline   Reply With Quote
Old 03-15-2007, 05:19 AM   #6
Tech Master
 
MassiveMods's Avatar
 
Join Date: Jan 2006
Location: Sydney
Posts: 1,977
Default

The hotter the better . If youre tuning for racing you cant rely on smoke out the pipe as a sign.. Different fuels will smoke more or some less, some not at all.

Many things determine the race temp on an engine so its a very broad question to answer.

I rarely temp my engine , i tune for performance till it chokes. I get just over 9 mins tank time in my MTX3. Ive run over 15 litres through it like this hitting temps in excess of 160 deg C the engine still has great pop .. Thats running 7% oil total..

Anyway i hope this helps some

Cheers MM
__________________
Engine development manager Rifling Pty Ltd. Nitro fuel designer : Neo + World record title holder 2012 Austalian Nationals 147.6 KPH , 1 st 2 nd and TQ Australian National Buggy titles 2012. Victorian State title 2012 Neo + , South Australian state title ON and Off Road 1/8 2012 Neo + :-) QLD State Titles 2012 1st buggy & trruggy + TQ Neo + MG66 RX7 1st Sportsman Class Truggy QLD State Titles 2012 !! Nitro Addicts Australia . com
MassiveMods is offline   Reply With Quote
Old 03-15-2007, 06:29 AM   #7
Tech Regular
 
Sirio2127's Avatar
 
Join Date: Jun 2005
Location: The land of two heads
Posts: 379
Trader Rating: 1 (100%+)
Send a message via MSN to Sirio2127
Default

Mark are you mad??. The guy asked a simple question Ya shore you can run engine like that. But under normal use you would stick around the 240 to 260 deg f and 120 to about 130 deg c for a 12 size engine. A .12 engines normaly runs hotter than a .21 engine i try to keep my 21 engines around 100 to 125 deg normaly about 110 or there abouts. Regards Jeremy.
Sirio2127 is offline   Reply With Quote
Old 03-15-2007, 07:47 AM   #8
Tech Master
 
vti-chris's Avatar
 
Join Date: Jan 2005
Location: Cyprus
Posts: 1,077
Trader Rating: 3 (100%+)
Default

Usually you want your engine to run around 160-170F more than the ambient temp is.
For example if it's 60F outsite then the safe engine temp is around 220-230.
If it's 90F then 250-260.
But this is all theory since the engines cooling head, the body, the gearing, the track,... all affect the engines temps.

Of course you can't run it for 5 minutes and say it's OK at 250 that it temps now and later on you go and run a 40min final and expect it to stay there...!!

There is also a point where the metals of the engine will start to wear out much faster at a given temp which for each engine this differes.
vti-chris is offline   Reply With Quote
Old 03-15-2007, 08:35 AM   #9
Tech Regular
 
RayJ's Avatar
 
Join Date: May 2003
Posts: 445
Default Temp Guns and Engine Tuning.

Tuning by temperature depends on alot of variables. Temp Guns as well. I have seen temp swings of 40 degrees F between guns. Also the method on how someone temps it is another factor. I use an Exergen 501, and try and temp it the same way each time. I make sure the cone is perpendicular to the head entering the cooling head.

If you use a temp gun.........use the same one each time. It will help you gauge a baseline reading on that motor.........and that particular day's ambient temps. For mains, you might want to start the motor a tad rich. Perhaps an hour or two richer on the top end. Many motors will come in 20 to 30 degrees hotter after ten to fifteen minutes of hard running. If your on the threshhold of too lean before a main........you might come in overlean during the main.

I know this topic was about specific temp...........but some motors run great at 240...........some won't even get out of there own way unless at 280(.12's that is). Depends on the motor.
RayJ is offline   Reply With Quote
Old 03-15-2007, 08:42 AM   #10
Super Moderator
 
Marcos.J's Avatar
R/C Tech Elite Subscriber
 
Join Date: Sep 2003
Location: Semper Fi
Posts: 27,208
Trader Rating: 182 (100%+)
Default

tune the engine by performance ,not all by temperature,
Marcos.J is offline   Reply With Quote
Old 03-15-2007, 10:25 AM   #11
Tech Elite
 
rmdhawaii's Avatar
 
Join Date: Feb 2006
Posts: 3,804
Trader Rating: 4 (100%+)
Default

Quote:
Originally Posted by vti-chris
Usually you want your engine to run around 160-170F more than the ambient temp is.
For example if it's 60F outsite then the safe engine temp is around 220-230.
If it's 90F then 250-260.
But this is all theory since the engines cooling head, the body, the gearing, the track,... all affect the engines temps.

Of course you can't run it for 5 minutes and say it's OK at 250 that it temps now and later on you go and run a 40min final and expect it to stay there...!!

There is also a point where the metals of the engine will start to wear out much faster at a given temp which for each engine this differes.
Here in Hawaii, our temps are usually between 80-90F, give or take 5. That's why randay and I would say 240-260F.

Now days, given the different head designs and materials, it's hard to gauge what is accurate anymore - and you have to have a very accurate temp gun.

Our humidity swings quite a bit throughout the day. You have to fuss with the engine quite a bit. We only get 3 minutes of warm-up on the track to figure out how the humidity has changed the tune of our engines and then figure out how much to turn the HSN just before the start of the race. If you know your engines well enough, you can guess-timate what the settings should be on the starter box. If you don't know your engines, guess-timating can be a bad thing.

IMO, temp-ing is good to help tune your engine, but should not be the only means by which you tune your engine. Tune for performance first and then make sure you're not about to blow up your engine by taking the temp. Well, that's how I do it.
__________________
Nitro Knowledge Base: http://nitrokb.netne.net
My YouTube Channel: http://www.youtube.com/nitrokb -> Lots of on-road nitro & eletric action + some off-road as well
My Flickr Photostream: http://www.flickr.com/photos/nitrokb/
Kyosho V-ONE RRR WC (x2) \ XRAY T2'007 \ Also owned: XRAY NT1 & Mugen MTX-4

Last edited by rmdhawaii; 03-15-2007 at 12:12 PM.
rmdhawaii is offline   Reply With Quote
Old 03-15-2007, 11:44 AM   #12
Tech Master
 
vti-chris's Avatar
 
Join Date: Jan 2005
Location: Cyprus
Posts: 1,077
Trader Rating: 3 (100%+)
Default

It's true you can't tune for performance and worry about temps...it will always be high...at least in most engines and most places.
That's why engine manufacturers keep increasing the size of the cooling head.
For example the new O.S. speed, the new O.S. VG, the RB S3, Radical, SH, ...
You can't have the same cooling head for all over the world.
In very cold climates you might need a head of an on-road engine...and on hot climates you might need an off road head on an on-road engine to keep the temps down.

You have to make sure that you have the right cooling head for the climate you race at.IF you care about your engines...!!!
The best case is to have the temps at a safe level and still be able to tune for performance.
vti-chris is offline   Reply With Quote
Old 03-15-2007, 04:20 PM   #13
Tech Regular
 
Sirio2127's Avatar
 
Join Date: Jun 2005
Location: The land of two heads
Posts: 379
Trader Rating: 1 (100%+)
Send a message via MSN to Sirio2127
Default

I normaly tune my engines to i have a good paformance and then do a few laps and just check the temp if i feel its to high for the condishions ill ritchen it. you can not tune an engine to temp but i have "ruff" temp ranges i try to stay with in. Regards Jeremy.
Sirio2127 is offline   Reply With Quote
Old 03-15-2007, 04:29 PM   #14
Tech Elite
 
Racing4Evo's Avatar
 
Join Date: Sep 2002
Location: SoCal
Posts: 2,118
Trader Rating: 2 (100%+)
Send a message via AIM to Racing4Evo
Default

Quote:
Originally Posted by rmdhawaii
Tune for performance first and then make sure you're not about to blow up your engine by taking the temp. Well, that's how I do it.
That's the way to do it.
Racing4Evo is offline   Reply With Quote
Old 03-15-2007, 04:41 PM   #15
Tech Addict
 
Join Date: Jan 2007
Posts: 660
Default

I got all that I was wondering if there was a point where I should say "that's too much"
__________________
Kyosho V-One RRR - JP Modified Mugen X12 - GQ Racing Tires - Futaba servos - KO Helios w/Spektrum Pro - Maxy's Fuel
Losi 8ight 2.0 RTR for fun times
Dredd is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
TC Tires and Temp. Range gt3angel Electric On-Road 6 08-14-2008 04:43 PM
NOVAROSSI BASIC ENGINE RANGE N21-3T jca2000au Onroad Nitro Engine Zone 1 12-03-2007 04:31 AM
Engine Temp spooner Monster Trucks 1 04-24-2007 07:01 PM
Temp Range? Mann2006 Monster Trucks 2 11-01-2006 09:16 AM
Increasing radio range? Or which radios have longer range if any? VN-TEC Nitro On-Road 23 12-13-2001 09:29 AM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 02:03 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net