L206 ar3910x sparkplug fake?

H

hickmankrt04

New member
hello any one else having problems with AR3910x spark plug?
client go DQed for having plug with electrode a little off center.
Tech told him it lets motor rev past 6050 rpm's ? rumor is there non Autolite plugs out there ???
 
Personally , i think its crap... i am just posting to get views . As far as i know the coil shuts off spark ,
so unless the plug is raging hot and motor is dieseling it not possible...???
 
Did the tech man show him the Briggs rule that he didn’t pass? Did the tech man check to see if his rev limiter didn’t work by starting the engine and checking it? Or did the incompetent tech man just DQ an innocent racer? There are no fake spark plugs. I’d rather pass 100 cheaters than DQ someone not cheating. I wish more tech men had that philosophy.
 
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I think a spec. spark plug is about the most stupid rule
they could come up with. If there was 1/2 h.p. difference
between plugs they might have a point.
Is there a spec. oil ? A spec. oil quantity ? Spec. mounting
bolts for the engine mount ?
Makes zero sense.
 
Having a spec spark plug makes sense when you have an ignition system that limits RPMs. The sprak plug IS the easiest way to cheat that rev limiter.

Yes, minimizing the gap will allow the plug to spark even when the coil is trying to cut spark. I have seen it both accidentally on the dyno with a plug that was bad AND on the track with a cheating competitor.

Now, to the best of my knowledge, there is no rule in the Briggs rule book yet. Cup Karts implemented one, so if your track/club uses their rulebook then there is a rule. However, like gary10 said, this is an easy check of the motor and/or tach to see if this was an actual performance advantage or an innocent mistake.
 
I’ve seen many plugs manufactured off Center where the gap is .016-.020” on one side. I believe the rule is .0185 which was chosen because a pin gauge already existed for the carb that size. It’s not some “magic number” where something makes it illegal. More a reference point.
 
gary10 said:
I’ve seen many plugs manufactured off Center where the gap is .016-.020” on one side. I believe the rule is .0185 which was chosen because a pin gauge already existed for the carb that size. It’s not some “magic number” where something makes it illegal. More a reference point.
Click to expand...

Agreed. Like I said, easy to prove/disprove performance advantage (and intent). Check their tach. Check the plug to see if it was manufactured off center or if one prong was "bent in". Check their gear ratio to see if they were trying to utilize those extra RPMs. All easy ways to figure out what was actually going on.
 
Biggest question is why does this track have a rpm rule of 6050 on a lo206? Was he on the limiter? Was he found past 6050 by his tach?
 
My question is why the 6050 rpm rule? This does not agree with the latest 206 rules.

From the 2022 Briggs ruleset:
30. Ignition System
a. Unaltered B&S stock ignition part #555718 is mandatory. Only “GREEN” ignition module allowed. Maximum RPM: 6,150.
 
He’s not saying they have a rev limiter rule. He’s saying the tighter plug gap let’s the limiter go higher
 
The old plug could be short gaped & impede the rev limiter. The 6,050 was probably a tipo. If you try it with the new plugs it is very
obvious what has been done, you do not have to measure anything.
 
Ok, I was going to stay out of this but here goes. I do tech for Cup karts, street races and a couple of tracks. This all started with the champion plug and guys were taking the carbon resistor out of it and replacing it with a solid copper wire and then by setting the plug gap at .005" you could actually turn 3300 to 3400 rpms. Very useful on big tracks. I personally have seen 5 DQs for altering the plug between Cup Karts, street races and others. The first clue to catch them guys was they would not be running a tach. And you cannot run a kart on a stand and get an accurate rpm because when they are free wheeling sometimes they will go over the limit. Does it work? I took my grandson to a couple different races down South during the winter and pitted next to some friends. Two of those guys smoked the field, and after tech (i was not working) which was a heads off inspection, they told me they had altered the plug. Cup Karts tried to persuade Briggs to write some specs on the Champion but instead went to the Autolite plug. Guess what, there is no resistor in the Autolite but I've already seen 4 plugs that the outside electrodes were bent in to lessen the gap, plus years ago in the clone days you could buy that plug in a longer length. Briggs actually makes a gauge to check the gap but only a couple of people have them ( i have asked 5 times and still don't have one). and then to add to the problem, and SOME BRAND NEW PLUGS WILL NOT PASS TECH. A good techman must look at the plug very close to determine if the plug was altered on purpose or just out of spec from the factory. By the way the internal circuits of the coil has been redesigned to eliminate the problem. Sometimes you just have to confiscate the plug and give him a new one and send him happily on his way. Let me be clear here. Cup karts is not trying to rule the class but if Briggs won't address the problem then Cup karts will address the issue in their rules. PS just wait till you see my post on whats going on with the heads, coming in a few days.
 
^ Thank you, Bob, for clearing this up.
I'll add that while it isn't in the current Briggs rule set, I suspect that it could be added as I think this has become an even greater problem now than with the old Champion plug.
There are a couple of ways I have seen these plugs modified -- I'm not going to share that info openly...BUT, suffice to say, it needs addressed because I've seen some come illegal from the factory too.
Like Derek, I found out real quick when an LO206 engine with a rev limiter ran away from me on the dyno. LOL
Trust me, there is a real advantage to turning the engine higher rpm if you can.
Swap the plug and wa-la, back to 6040 or 6050 again.
One plug that I have in my possession, that I share with others as an example at our tech seminars, has one of the ground prongs stamped incorrectly from the factory and is considerably closer to the center electrode than the other three. Another was "massaged" and is pretty obviously altered.

Dan is aware of the problem, same with the heads...I'll wait to see what Bob posts about that before I comment any further. :)


-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
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33 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
 
Some of the comments on plugs make my point.
The rev limiter is the qualifying element not the
spark plug. If your plug is screwy and the rev
limit is exceeded then the engine is illegal. Forget
the spec plug and trust in the rev limiter to determine
legal or illegal.
 
Bumpy said:
I think a spec. spark plug is about the most stupid rule
they could come up with. If there was 1/2 h.p. difference
between plugs they might have a point.
Is there a spec. oil ? A spec. oil quantity ? Spec. mounting
bolts for the engine mount ?
Makes zero sense.
Click to expand...
There are some spark plugs that do make significantly more power. Very few people know about them. Everything else is spec in the LO206 engine , so the spark plug might should be as well.
 
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