Glow Plug Differences?

[Skwerly]

My Traxxas manual says to replace the plug with #3231, but on the LHS website, I see #3230 and #3232, both claiming to work in Traxxas vehicles.

Of course, this begs the question, what is the difference between model numbers, and what should I, as a complete noob, know about them? Thanks in advance!

 

[RC Addict]

The 3230 is the standard "hot" plug and the 3232 is the heavy-duty medium plug.

 

[TWOCANE]

if you are running 20% like you should in you mill all of the plugs will work.I ran a 3232 med/hot plug that is heavy duty also.

 

[Lessen]

Plugs that are referred to as being "hotter" have smaller guage wire than plugs that are considered "colder". The thicker wire of the "colder" plug retains heat longer, this is helpful for larger displacement engines that cool more efficently. Likewise, "hotter" plugs have thinner guage wire that cools quicker than "cold" plugs which is helpful for smaller displacemet engines that tend to retain more heat because of their lesser ability to dissipate it. Rule of thumb is that "cold" plugs are for big blocks like .21 and larger and "hotter" plugs are for smaller engines like .12's and .15's.

 

[Skwerly]

Plugs that are referred to as being "hotter" have smaller guage wire than plugs that are considered "colder". The thicker wire of the "colder" plug retains heat longer, this is helpful for larger displacement engines that cool more efficently. Likewise, "hotter" plugs have thinner guage wire that cools quicker than "cold" plugs which is helpful for smaller displacemet engines that tend to retain more heat because of their lesser ability to dissipate it. Rule of thumb is that "cold" plugs are for big blocks like .21 and larger and "hotter" plugs are for smaller engines like .12's and .15's.

Ah! Ok, cool!

Thanks guys, appreciate. I bought some weird plug on my last trip to the LHS, because the guy behind the counter said it should work fine. I haven't tried it in the car yet, but I put it in my "bash box". I can't remember the # offhand, but it was surely not a 323_ number hahaha. It appears identical to all the other plugs I have, though.

 

[TWOCANE]

Run it! but if your tuning then use the GP you are going to be useing all the time.

 

[Skwerly]

LOL ok, will do, thanks!

 

[Racer 1966]

Plugs that are referred to as being "hotter" have smaller guage wire than plugs that are considered "colder". The thicker wire of the "colder" plug retains heat longer, this is helpful for larger displacement engines that cool more efficently. Likewise, "hotter" plugs have thinner guage wire that cools quicker than "cold" plugs which is helpful for smaller displacemet engines that tend to retain more heat because of their lesser ability to dissipate it. Rule of thumb is that "cold" plugs are for big blocks like .21 and larger and "hotter" plugs are for smaller engines like .12's and .15's.

Well Josh I hate to argue but I disagree with your assessment. The difference has more to do with nitro content and controlling ignition timing rather than heat dissipation and engine size.

Nitro takes less temperature to ignite, so the higher your nitro content gets the cooler your plug can be. Running a hot plug with high nitro is like advancing the timing too far and causing detonation. Likewise, low nitro with a cold plug will result in a retarded timing condition.
Either way robs power and causes excessive engine temps.

One other thing that goes along with this though, is the compression ratio in the engine. That's what is being changed by adding or removing shims under the head.

These two things have to work together to get the best performance from an engine.

This is my understanding of things and what makes the most sense to me. Your results may vary :

 

[Skwerly]

LOL, thanks! I will take any information I get! The way it usually works is, everyone is correct on some level, and when all the information is combined, it is possible to essentially know everything about the subject hahaha.

Very cool site, I am still amazed at the time you all take to help us noobs out .

 

[Lessen]

My bad, I had the heat dissipation qualities according to size backwards. But according to O.S., engine heat dissipation does play a role as other factors do as well such as nitro content like you pointed out and other things like temperature, track conditions etc. From O.S. website...

Size matters to glow plugs. What size is your engine? A .12? .15? .21? Big engines have more mass and retain heat better. Smaller, lighter engines don't, and need the help a hotter plug can offer.

Guideline 2: The smaller the engine, the hotter the plug.

Running a hot plug with high nitro is like advancing the timing too far and causing detonation. Likewise, low nitro with a cold plug will result in a retarded timing condition.

I agree with that, certainly. From O.S. website...

What's the nitro percentage in your fuel? High-nitro fuels produce more power than low-nitro fuels, but also produce more heat.
Guideline 3: The higher the nitro content, the colder the plug.

 

[Skwerly]

Hehe, I'm running a Traxxas 2.5, so I believe it is a .15 engine.

I found the packaging for the glow plug the guy at the hobby shop pushed on me:

It's a Thunderbolt Heavy Duty Plug, item No. 115545, if that means anything to any of ya .

 

[Meldarion]

Lol just to double check then, because i had been looking at plugs and was amazed at the different types you can get, If i am running a .18 with 16% nitro content fuel, not fully broken in yet, and atm i am using the stock plug, what type of plug should i replace it with if it wears out ? ^^