RunRyder RC
WATCH
 1 page 720 views Post Reply
Home✈️Aircraft🚁HelicopterGasser Model RC HelicoptersEngines › G240rc different spark plug
05-09-2015 12:40 AM  6 years ago
Topic Vote0Post 1
mustang67ford

rrKey Veteran

Central Pennsylvania

MyPosts All Forum Topic
G240rc different spark plug
Happened to be looking thru the owners manual. It notes the stock plug as a cmr7h. But it then notes a Cr8hix for racing and a Cmr6h as a hotter plug. Anybody ever try the alternatives?
Team HeliProz - Retired
AMA #513507
IRCHA #4011
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
05-09-2015 01:07 AM  6 years ago
turboomni

rrProfessor

East of the Equator

MyPosts All Forum Topic
I personally wouldn't go to a hotter plug when flying in the summer especially with a puh style. You could try the racing plug which I presume is cooler. But if you have no problems I wouldn't bother.Setup is everything, All my heli's can fly far better than I can pilot them
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
05-09-2015 01:38 AM  6 years ago
mustang67ford

rrKey Veteran

Central Pennsylvania

MyPosts All Forum Topic
No problems. RC style motor. Just inquiring.Team HeliProz - Retired
AMA #513507
IRCHA #4011
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
05-09-2015 01:57 AM  6 years ago
turboomni

rrProfessor

East of the Equator

MyPosts All Forum Topic
On second thought on those really hot hot humid days that will soon be upon us it might be interesting to try the cooler plug.Setup is everything, All my heli's can fly far better than I can pilot them
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
05-09-2015 03:36 PM  6 years ago
BeltFedBrowning

rrKey Veteran

Kansas City

MyPosts All Forum Topic
...
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
05-09-2015 04:19 PM  6 years ago
turboomni

rrProfessor

East of the Equator

MyPosts All Forum Topic
What I thought especially with an air cooled engine on extremely hot humid days if you try a cooler plug and it works well [no fouling etc] then it couldn't hurt to use it. On my modified turbo car running 20 psi boost on pump premium I would use a cold plug as part of a plan to combat detonation along with intercooling and water methanol injection like they did on WW2 airplane engines.
The Zenoahs have very low compression ratios so it can run very low octane levels like 50 octane coleman fuel so I consider 89 pump gas premium fuel for a gasser.
Setup is everything, All my heli's can fly far better than I can pilot them
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
05-09-2015 04:30 PM  6 years ago
RM3

rrElite Veteran

Killeen, Texas - USA

MyPosts All Forum Topic
Ive never really understood the concept of hot or cool "spark" plugs... nitro plugs yes... spark ignition no.

and here is why.

they talk about detonation etc... but detonation is caused by combustion of the fuel mix due to compression which is mostly controlled by additives in the fuel and to a point the compression ratio. the fuel additives basically increase its resistance to ignition due to elevated temperatures and pressures.

now this thing about fouling... thats more to do with whats being burnt in the chamber and when.

I think the only thing thats makes any difference is the electrode metal and its ability to freely emit and conduct electrons... sort of like hafnium is used at the tips of plasma cutters electrodes... as well as the gap distance itself.

maybe hot or cold spark plugs have more to do with the fuel they are designed to operate with...
showing a preference will only get you into trouble, 90% of everything is crap...
SHARE  PM  EMAIL  Attn:RR  Quote
05-09-2015 04:33 PM  6 years ago
turboomni

rrProfessor

East of the Equator

MyPosts All Forum Topic
I think a plug that is too hot under extreme conditions retains too much heat and can cause a hot spot for detonation.

using lots of boost or compression bad fuel for the requirement lugging the engine, timing, timing advance,, there are many variables. A cold plug wont give you more power ,it will give back possibly the power that was robbed from detonation.

As far a fouling if a plug is too cold it will not burn off the deposits and foul. Of course it could happen to a hot plug with too rich a mixture too. Too lean a mixture and it is clean as a whistle!! Way too lean and under a magnifying glass you could see little blobs of metal stuck to the porcelain with is melted piston deposits from detonation.
You can also have so much carbon buildup in the cylinders that they will glow and fire a charge before it is supposed to.

I am not pretending to be an expert ,,I am not. This is the way I presently under stand it.
Setup is everything, All my heli's can fly far better than I can pilot them
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
05-10-2015 12:17 AM  6 years ago
turboomni

rrProfessor

East of the Equator

MyPosts All Forum Topic
Here's a diagram of a hot and cold plug.

https://www.google.com/search?q=Hea...tml%3B629%3B398
Setup is everything, All my heli's can fly far better than I can pilot them
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 1 page 720 views Post Reply
Home✈️Aircraft🚁HelicopterGasser Model RC HelicoptersEngines › G240rc different spark plug
Print TOPIC

 1  Topic Subscribe

Thursday, July 29 - 9:51 pm - Copyright © 2000-2021 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online