Glow plugs for Traxxas 3.3

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Juggalo Racing 73

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Anyone got good recommendations for good glow plugs,, I have blown out the few Traxxas plugs I have, looking for a tougher plug with a little more life to it
 
Anyone got good recommendations for good glow plugs,, I have blown out the few Traxxas plugs I have, looking for a tougher plug with a little more life to it
The O.S. LC4 is a direct replacement for the 3232X if I'm not mistaken.
 
Anyone got good recommendations for good glow plugs,, I have blown out the few Traxxas plugs I have, looking for a tougher plug with a little more life to it
In my 4tech 3.3, (Highly modified engine) 12,000 squish band height, timing, opened up boost ports, narrowed con rod, skirted piston, drilled through crank weight "To throw fuel up into the case", stuff like that.
Anyways, I ran 30% and 40% FHS Oils Red Max fuel and blew OS max plugs all the time.

I decided to run the K&B long plugs with the 30%, and for 40% I ran the K&B short idle bar plug.

Idle bar plugs have a bar that goes across the bottom of the plug and protects the coil. With the 40% nitro I used the short idle bar to keep the coil intact due to the higher rpm of the extra 10% nitro without having to re-shim the motor's squish band.
With the 40% if I run a K&B long plug, it would run just the same except it would compress the coil, but never suck it out or kill the engine. So, I went with the short medium Idle Bar plug for a few different reasons,
1) To give me a little less compression and save the coil and the idle bar helped from lowering the compression too much.
2) The idle bar helps keep the coil glowing hotter as it kind of diverts the updraft from the piston moving upward, so the coil glows hotter and doesn't get pushed up into the plugs body "Compressed".
Other brands have idle bar plugs, but I use the K&B plugs because I can file a small clean spot on the bottom of the blackish colored plug body, make a few high-speed passes and pull the plug and look at the clean filed spot to check for "dry/burned lean" run or "Wet/clean rich" settings.

Usually when an engine is eating the coil, it's from a too lean setting, or too high of compression for the nitro content. "In layman's terms" those are the two common reasons a plug will blow.

This of course worked for me, and I can't say if it will help you or not.

Available at Mecoa
Screenshot 2022-10-16 202024.jpg
 
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In my 4tech 3.3, (Highly modified engine) 12,000 squish band height, timing, opened up boost ports, narrowed con rod, skirted piston, drilled through crank weight "To throw fuel up into the case", stuff like that.
Anyways, I ran 30% and 40% FHS Oils Red Max fuel and blew OS max plugs all the time.

I decided to run the K&B long plugs with the 30%, and for 40% I ran the K&B short idle bar plug.

Idle bar plugs have a bar that goes across the bottom of the plug and protects the coil. With the 40% nitro I used the short idle bar to keep the coil intact due to the higher rpm of the extra 10% nitro without having to re-shim the motor's squish band.
With the 40% if I run a K&B long plug, it would run just the same except it would compress the coil, but never suck it out or kill the engine. So, I went with the short medium Idle Bar plug for a few different reasons,
1) To give me a little less compression and save the coil and the idle bar helped from lowering the compression too much.
2) The idle bar helps keep the coil glowing hotter as it kind of diverts the updraft from the piston moving upward, so the coil glows hotter and doesn't get pushed up into the plugs body "Compressed".
Other brands have idle bar plugs, but I use the K&B plugs because I can file a small clean spot on the bottom of the blackish colored plug body, make a few high-speed passes and pull the plug and look at the clean filed spot to check for "dry/burned lean" run or "Wet/clean rich" settings.

Usually when an engine is eating the coil, it's from a too lean setting, or too high of compression for the nitro content. "In layman's terms" those are the two common reasons a plug will blow.

This of course worked for me, and I can't say if it will help you or not.

Available at Mecoa
View attachment 154367
Nice,, will be totally looking into those plugs,, Thanks for the feed back
 
here is a link to the mecoa plug page.
http://www.mecoa.com/acc/glowplug/glowplug.htm

In the pic I supplied the top two plugs are K&B HP plugs, the bottom plugs are K&B idle bar plugs.
mecoa has a wealth of general info if you look around the web sight. Plus a wealth of parts too.
Awesome,, Thanks!! I changed fuels to VP 20% and it roasted the glow plugs in just a couple of tanks
 
Awesome,, Thanks!! I changed fuels to VP 20% and it roasted the glow plugs in just a couple of tanks
I have been using KB and HP plugs for 40 plus years they are robust to say the least. When I do use random OS or other plugs, they get mangled.
FOX makes some really good plugs too, I think K&B manufactured FOX plugs too. Mecoa is K&B, Mecoa bought K&B a long time ago.

The 3.3 engines have varying squish bands (Sloppy work from the factory). I have had many 3.3 engines and they were all different squish band heights. If I remember right, I think Traxxas says 16000 "Sixteen thousandths" is what's recommended for optimal use and longevity. May I ask if you ever checked the squish band? And if so, what is the reading?
Like me at 12-13ish000th (Twelve to thirteen-ish thousandths) I'm doing that on purpose to build power and knew mangling plugs would be an issue considering the high nitro content I use.
(I run my 4tech in a huge nascar style loop) where I can get it up to speed and keep it at full throttle.
I found that between 14000th and 18000th the plugs lasted 20 to 30 tanks on 30-40% nitro (No joke). I run FHS Oils Red Max fuel.

Oh yeah, I forgot to mention, as far as cold and hot plugs go, I never worried about that, some do but for me it never really mattered either way. The differences weren't that great of a deal.

Have you checked your squish band height? It might be too tight. I don't think you're running it too lean so maybe your deck height is too tight.
 
I have been using KB and HP plugs for 40 plus years they are robust to say the least. When I do use random OS or other plugs, they get mangled.
FOX makes some really good plugs too, I think K&B manufactured FOX plugs too. Mecoa is K&B, Mecoa bought K&B a long time ago.

The 3.3 engines have varying squish bands (Sloppy work from the factory). I have had many 3.3 engines and they were all different squish band heights. If I remember right, I think Traxxas says 16000 "Sixteen thousandths" is what's recommended for optimal use and longevity. May I ask if you ever checked the squish band? And if so, what is the reading?
Like me at 12-13ish000th (Twelve to thirteen-ish thousandths) I'm doing that on purpose to build power and knew mangling plugs would be an issue considering the high nitro content I use.
(I run my 4tech in a huge nascar style loop) where I can get it up to speed and keep it at full throttle.
I found that between 14000th and 18000th the plugs lasted 20 to 30 tanks on 30-40% nitro (No joke). I run FHS Oils Red Max fuel.

Oh yeah, I forgot to mention, as far as cold and hot plugs go, I never worried about that, some do but for me it never really mattered either way. The differences weren't that great of a deal.

Have you checked your squish band height? It might be too tight. I don't think you're running it too lean so maybe your deck height is too tight.
Have not had a chance to really check any of that yet,just got the engine broken in a few days ago
 
Have not had a chance to really check any of that yet,just got the engine broken in a few days ago
Oh it's a new engine, new engines blow plugs, just part of the hobby.
Do as the manual says for break in. Don't listen to what I am about to say.

I don't break my engines in. I run them on the fuel I will use in the engine, I set the needle valve to just a fine hair rich and run them flat out while driving the car or boat wide open in a large nascar style loop where I can get lots of cooling air and not have to come off throttle (I don't want the tight piston to sleeve fit to shut the engine off so I keep wide open) for the whole tank. Usually, a tank is all that I need. The next tank, engine still warm I set a race needle setting and boom ready to go. But that's just me. I do it this way because K&B engines the break in procedure is that way for onroad and marine engines. Nothing different between engines and made from the same materials, the way I see it.
I never understood why people use bench break in procedures and go through 2 to 3 gallons of fuel (Not saying you are bench breaking in or not) just saying, sure some higher buck engines have very tight piston to sleeve tolerances and such but still, I break them in on the run. Rossi and CMB engines I do the same but that takes a few tanks to break in.

If your engine is new, just be patient the plug life might get better. I didn't realize it was a new engine, sorry.
Sucks to score the sleeve with blown coils, I know. One of the reasons I don't follow break in procedures. Not to mention the 40 plus years of nitro engines I had. I'm not rich by any means but if I blow an engine up, I can get another in three weeks (not the end of the world), that's how I look at it. But I never hurt an engine breaking them in the way the engine will be run. Most engines are run at the factory to make sure they run, and such are mostly broken in anyways to a point. I guess it's the old school in me.

I know I'm taking a chance at wearing the chrome or nickel (ABC or ABN whatever the case might be per engine) out on the sleeve when I break in on the run, but it's the risk I take in order to go fast lol. I only worn out the top of the sleeve on 3 engines in my life breaking them in, in my life and at that the engines ran fine.
Simply put don't follow my example as the risk might outweigh the use of the engine. My engines are not bought to last, they are bought to go fast, but usually they last too.
 
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This is where and why I break my engines in the way I do, this is from the manual that comes with the K&B 3.5cc rear exhaust engines (It's actually a front exhaust engine but we call them rear as the exhaust points rearward) when in a boat. notice the break in procedure. Pic is of the engine. Same engine as the on-road engine from K&B, except the car engine has a heat sink head. keep in mind our tanks hold 10 to 15 minute run times so I only usually do one tank.
(I don't make this sht up LOL)
basically, it's saying start the engine and run it and don't stop. Instructions are the same for K&B car engines as well and are the exact same engines except for the heat sink heads.

"It's not saying our engines", it's saying "An ABC type engine" So I follow these guidelines. It also recommends between 25 and 50% nitro. meaning you can break in on 50% if ya want. Rule of thumb is to break the engine in with the fuel and content you will run. It's not uncommon for boat engines to run 65% plus during heat racing. I run 30 to 40% in my 3.3 because it's cost effective. The smaller the engine the higher the % can be, small engines love nitro....
The younger generation don't know this stuff because they never lived it back in the 70's and 80's and only know what todays rtr manuals state, keeping in mind with rtr the companies want the customer to have a no return, no hassle sale so the manufactures make certain to lengthen the break in periods, eating up valuable warranty time, to help the new customer get accustomed to the needle valve settings as a learning tool. All the while the customer is spending lots of money on their fuels and such and at the same time not enjoying the product. IMO, it's a marketing strategy, much like "After Run Oil" Marvels Mystery oil does the exact same thing at a way cheaper price.
So, I get a lot of arguing from some of the stuff I say and do. LOL So don't follow anything I say, take what you can and use what ya can.

1666018937354.png

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The LC4 is a medium hot plug just like the 2525x. Just FYI.

I need to buy some LC4's ,I bought some LC3's last time ,they worked but didnt
last an my 5.9 requires a cooler plug ,the 28 engine did not fair good with the LC3 ,
so I looked at the 5.9 manual it said the engine takes a cool plug ,so I will try a medium
plug like the LC4!
 

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