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 06-28-2010, 04:18 PM   #1
Tech Elite
 
Chickentrader's Avatar
 
Join Date: Feb 2007
Location: Landsborough, Queensland, Australia.
Posts: 2,142
Trader Rating: 13 (100%+)
Default Getting 5 minutes & exhaust cooler

We're having trouble getting 5 minutes out of a tank. I that the fuel we use is the culprit; but it makes our engines run cooler, and have the maximum nitro content allowed in Australia. We don't want to change fuel, so we are looking for way to stop us running out of fuel on the last lap without re-fueling. Do exhaust coolers really work to improve fuel economy?

I'm not the smartest cookie around, and I have trouble understanding how it could. The pressure at each end of a hose will be equal at both ends to my way of thinking; regardless of its length, or devices between either end (other than diaphragm valves).

Could someone enlighten me about this, or has anyone had experiences where exhaust coolers have definitely helped?

Kindest regards,
Lars,
__________________
Support your local RC stores - they support our sport!
Social media The empowerment of the small individual to enforce democratic process at the expense of dishonesty.
Chickentrader is offline   Reply With Quote
Old 06-28-2010, 04:30 PM   #2
Tech Elite
 
Chickentrader's Avatar
 
Join Date: Feb 2007
Location: Landsborough, Queensland, Australia.
Posts: 2,142
Trader Rating: 13 (100%+)
Default

Picture of exhaust cooler: If the pictured doesn't show, it can be found by clicking on this link: http://i498.photobucket.com/albums/r...austcooler.jpg

Kindest regards,
Lars.
__________________
Support your local RC stores - they support our sport!
Social media The empowerment of the small individual to enforce democratic process at the expense of dishonesty.

Last edited by Chickentrader; 06-28-2010 at 04:33 PM. Reason: Add text
Chickentrader is offline   Reply With Quote
Old 06-28-2010, 04:33 PM   #3
Tech Regular
 
Join Date: Jul 2003
Posts: 478
Trader Rating: 1 (100%+)
Default

Quote:
Originally Posted by Chickentrader View Post
We're having trouble getting 5 minutes out of a tank. I that the fuel we use is the culprit; but it makes our engines run cooler, and have the maximum nitro content allowed in Australia. We don't want to change fuel, so we are looking for way to stop us running out of fuel on the last lap without re-fueling. Do exhaust coolers really work to improve fuel economy?

I'm not the smartest cookie around, and I have trouble understanding how it could. The pressure at each end of a hose will be equal at both ends to my way of thinking; regardless of its length, or devices between either end (other than diaphragm valves).

Could someone enlighten me about this, or has anyone had experiences where exhaust coolers have definitely helped?

Kindest regards,
Lars,
the question everyone will ask is
what motor
what manifold
what exhaust
what glow plug
what head shimming
is there any mods done to the motor....

the exhaust cooler only gives a few seconds that is all.
engine temp is different for every motor do not be to concerned about it tune preformance not temp.
The_Keeper is offline   Reply With Quote
Old 06-28-2010, 04:46 PM   #4
Tech Elite
 
Chickentrader's Avatar
 
Join Date: Feb 2007
Location: Landsborough, Queensland, Australia.
Posts: 2,142
Trader Rating: 13 (100%+)
Default

Quote:
Originally Posted by The_Keeper View Post
the question everyone will ask is
what motor
what manifold
what exhaust
what glow plug
what head shimming
is there any mods done to the motor....

the exhaust cooler only gives a few seconds that is all.
engine temp is different for every motor do not be to concerned about it tune preformance not temp.
That's exactly what I would have thought about the exhaust cooler; but it would have put us across the line at Bayside on Sunday, and it is cutting it too fine. No mods, JPI exhaust & manifold (don't know which number), O.S.TZ, O.S.P7 plug (perhaps too cold?) No head shims. Perhaps we could still lean the top end a bit more, its not getting too hot.

Would an O.S. tuned pipe, or a hotter plug help you think? We usually run a Jammin Hyper EFRA 2645 exhaust; as it seems to make the engines run faster, but we're having the same fuel economy problems with that exhaust. We're planning to be at Brendale on Sunday, will you be there?

Kindest regards,
Lars.
__________________
Support your local RC stores - they support our sport!
Social media The empowerment of the small individual to enforce democratic process at the expense of dishonesty.
Chickentrader is offline   Reply With Quote
Old 06-28-2010, 05:51 PM   #5
Tech Lord
 
wingracer's Avatar
 
Join Date: Nov 2007
Posts: 12,861
Trader Rating: 24 (100%+)
Default

Add a head shim; go leaner.
__________________
Sean. Certified speed crazed mowron.
Team Shepherd USA
www.ashfordhobby.com
wingracer is offline   Reply With Quote
Old 06-29-2010, 04:19 AM   #6
Tech Fanatic
 
Alex Siddique's Avatar
 
Join Date: Nov 2007
Location: Central Coast , NSW Australia
Posts: 872
Trader Rating: 30 (97%+)
Send a message via MSN to Alex Siddique
Default

Few things to look into
Clutch And Gearing also affect the run time . And Can alter run time btw 5 to 40 sec . Also not having the bottom needle right effects run time majorly . Economy comes from bottom needle . A bigger exhaust gas outlet on the pipe will give more power but at the cost of run time another thing to look into for run time .
__________________
No Fucker's Taking my money O/s OR local :) :)
Alex Siddique is offline   Reply With Quote
Old 06-29-2010, 05:14 AM   #7
Tech Elite
 
Pattojnr's Avatar
 
Join Date: Apr 2006
Location: Perth Australia
Posts: 4,594
Trader Rating: 19 (100%+)
Default

Quote:
Originally Posted by Chickentrader View Post
That's exactly what I would have thought about the exhaust cooler; but it would have put us across the line at Bayside on Sunday, and it is cutting it too fine. No mods, JPI exhaust & manifold (don't know which number), O.S.TZ, O.S.P7 plug (perhaps too cold?) No head shims. Perhaps we could still lean the top end a bit more, its not getting too hot.

Would an O.S. tuned pipe, or a hotter plug help you think? We usually run a Jammin Hyper EFRA 2645 exhaust; as it seems to make the engines run faster, but we're having the same fuel economy problems with that exhaust. We're planning to be at Brendale on Sunday, will you be there?

Kindest regards,
Lars.
nova or Max 2601 or 2604 with med conical manifold should help. i have used 2652 nova pipe, and i dont get much more power but it uses more fuel. i really think these 2640+ pipes are really aimed for use with Ins Boxes.

added head shim can add more top end revvs, that with leaner mixture, a long straight could see other problems. OS TZ unmodded shold make run time easy, try different pipe and manifold, i have gained 20secs plus just from going back to the 2601.
__________________
Serpent - Walter RC
Serpent E Power ..... Serpent 747 Reds M3T
Serpent 966-TE Reds M7T .... S411ERYX Speedpassion 3.5T, T-Shox
Serpent 811-TE REDs R5T
Pattojnr is offline   Reply With Quote
Old 06-29-2010, 06:35 AM   #8
Tech Regular
 
musti72's Avatar
 
Join Date: Sep 2007
Location: Turkey
Posts: 442
Default

You can also try non conical manifolt...
__________________
Mustafa Alp

http://www.aytemizhobi.com
Turkish shop for: Serpent, Xceed, Sweep Racing, MyLaps
musti72 is offline   Reply With Quote
Old 06-29-2010, 04:24 PM   #9
Tech Elite
 
Chickentrader's Avatar
 
Join Date: Feb 2007
Location: Landsborough, Queensland, Australia.
Posts: 2,142
Trader Rating: 13 (100%+)
Default

]Many thanks to those that contributed to this, I have learned a lot from it. I did not know that most of the fuel economy comes from bottom end; thanks for that info, it makes sense to me. However; I feel that the bottom end is right, its set where the revs are just starting to increase at about 1mm throttle from low idling speed, and it gives instant response from low idling speed or higher idling speed (http://www.infinity-hobby.com/main/a...rticles_id=172) at starting. I never muck around with the mid range needle, as I have no idea of how to set it, could adjusting that help?

The gearing and clutch settings are also obviously very important for fuel economy; but the gearing and clutch settings have been set to what my boy wants, after some testing. We dont really want to change it; Id be more comfortable with an extra fuel stop than to change to something hes not 100% happy with.

I will add a shim and get a 2601 exhaust with 5 & 7 fin manifolds, and try that. Also the engine could possibly run with a little leaner top end.

It is interesting that not many here seem to be convinced that exhaust gas coolers would be a significant help to fuel economy. I found an article about it with an actual test from RC Tech Magazine () , after I started this thread. It claims that run time in a helicopter increased by about 33%, and theorises of how it makes it better. Interesting reading; Im still a sceptic, but we will use exhaust coolers from now on.

Kindest regards,
Lars.
__________________
Support your local RC stores - they support our sport!
Social media The empowerment of the small individual to enforce democratic process at the expense of dishonesty.
Chickentrader is offline   Reply With Quote
Old 02-20-2012, 09:03 PM   #10
Tech Elite
 
Arahawak's Avatar
 
Join Date: May 2006
Location: A.D. 2030
Posts: 3,444
Trader Rating: 32 (100%+)
Default

I know this kinda of an old thread..

But does anybody knows who besides novarossi makes the exhaust coolers?
Nova's are way too expensive
__________________
Support Bacteria - its the only culture some people have!
Arahawak is offline   Reply With Quote
Old 02-20-2012, 10:54 PM   #11
Tech Master
 
chippy's Avatar
 
Join Date: Jan 2002
Location: NSW OZ
Posts: 1,492
Trader Rating: 4 (100%+)
Default

Quote:
Originally Posted by Arahawak View Post
I know this kinda of an old thread..

But does anybody knows who besides novarossi makes the exhaust coolers?
Nova's are way too expensive
Titan make one is around $16 U.S
chippy is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
1/8 scale off-road Electrics adrictan Singapore R/C Racers 6612 06-12-2012 06:02 PM



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