Spark Plugs for Open 2 Cycles


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I’m looking for spark plugs. Yes, the common answer is “look back in the archives” but we all know Autolite 2414’s, 2413’s, AG203’s, AG403’s, Denso W31EN’s and W34EN’s are non existent these days and those who have them aren’t letting them go or aren’t speaking up. The cross reference website is ambiguous when these plugs are looked up and is rather inaccurate for heat ranges and recessed/non recessed electrodes. I have a 119 TT75 on alcohol and a 116 Atomic Rotary on alcohol as well. What are VIABLE plugs that are still in production that will suite these motors for both cold and hot weather racing conditions?
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yeah, what a freakin zoo it is trying to track down plugs for the 2 cycles, if ive done my searching and cross referencing correctly, the NGK B10EGP is about $12 each, a NGK R7376-10 appears to cross match, its an iridium plug, about $28/ea on


Dawg 89
Gap less marine plugs could be an option , I've only seen short ones though .
Even at 12 bucks one and a spare should get through a season .


I believe the autolite stock# is either 5252 or 5225 for the 2413. Pretty shure it's 5252. The easiest way out is to go to you're local NAPA and have them order them( sit there and make sure they order the retracted tip plugs) I would not consider the regular plug. Depending on how much you race and how good you can tune will determine how many it will take to get you through a season. Ps don't use the pricey plugs to flush just my 12 $ worth lol. Chuck


I think the Denso plugs are still available? Yes, the Autolite sidegap plugs are really hard to get but they do pop up from time to time, the hoarders do have them. Look for them in a Motorcraft brand too.
For sure don't purge with the rare plugs, save those for racing. If you run alky I sure hope you are purging. Like you said, I have my own and they are not available. Its like a treasure hunt! Good luck.

Might buy a couple of these till you find better.
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Ted Hamilton

Helmet Painter / Racer
NGK here too. I like the BR9IX Iridiums, but they're a bit pricey. So I usually get the BR9 and BR10EG editions....
FOUND 5 EA N57R-4 ag403 ( SAME ) 1 EA W 31 denso-- 10 new plugs 80 + ship all for parilla 131 sudam! running a front motor top fuel car now and dont need them!l look us up on NDRL! boise idaho : night of fire! buy all or 1 for 9 $ ea
hilton framily racing!.