EVO spark plugs w/ removable top nut
EVO spark plugs w/ removable top nut
Hello,
Could you please help in below two matters:
1. Are this the most used/best spark plugs for our EVOs? Are there any other brands/models that will fit?
Champion RN12YC
Autolite 4265
NGK BPR5ES
2. I need a spark plug with removable top nut, and have some hard times finding it..
Thanks
BR
Marcel
Could you please help in below two matters:
1. Are this the most used/best spark plugs for our EVOs? Are there any other brands/models that will fit?
Champion RN12YC
Autolite 4265
NGK BPR5ES
2. I need a spark plug with removable top nut, and have some hard times finding it..
Thanks
BR
Marcel
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,586
Likes: 6,435
From: Honah Lee
The NGK BPR5ES top terminal screws off.
Just a sorta off topic but if you ever use a plug with this feature with the terminal screwed on, part of the setup is check gap and use a pair of pliers to tighten the terminal.
I was changing a set on a Toyota 4 cylinder and none of the plugs had the terminals or even threads. What was left of terminals was a thin aluminum tube in the sparkplug wire boot.
They obviously must have been a little loose and 50,000 volts jumping the gap did it's thing.
Just a sorta off topic but if you ever use a plug with this feature with the terminal screwed on, part of the setup is check gap and use a pair of pliers to tighten the terminal.
I was changing a set on a Toyota 4 cylinder and none of the plugs had the terminals or even threads. What was left of terminals was a thin aluminum tube in the sparkplug wire boot.
They obviously must have been a little loose and 50,000 volts jumping the gap did it's thing.
Last edited by Jackie Paper; Jan 26, 2026 at 07:12 AM.
Seasoned HDF Member
Joined: Jul 2014
Posts: 8,603
Likes: 3,374
From: Cental, MI
You have listed the three most Popular Plugs.. Pick One..
I have Used Autolite 4265 forever.. In the good ole days of American Made Champions, they were my choice..especially if older High Mileage engine. Champions were always good to recover from Oil Fouling... NGK Never would.. Autolites were most popular at DragStrip.. probably due to Cost vs Performance..
For the Import style (NGK) plug boot, the NGK plug, is Known to have removeable (threaded) Top Cap. I thought Champion and Autolite did Also...But..Would need to check New Production.
I have Used Autolite 4265 forever.. In the good ole days of American Made Champions, they were my choice..especially if older High Mileage engine. Champions were always good to recover from Oil Fouling... NGK Never would.. Autolites were most popular at DragStrip.. probably due to Cost vs Performance..
For the Import style (NGK) plug boot, the NGK plug, is Known to have removeable (threaded) Top Cap. I thought Champion and Autolite did Also...But..Would need to check New Production.
Last edited by Racepres; Jan 26, 2026 at 07:28 AM.
Grand HDF Member
Joined: Sep 2022
Posts: 4,470
Likes: 3,852
From: Florida
I am a zealot for 4264-4265 depending on heat range. I wanted to believe fancy spark plugs added magical power so I bought a number a few years ago. If you really wanna test them… Start opening the gap a little wider and then going full throttle. Keep widening until they cut out and then record the gap.
‘’Keep trying plug after plug and widening.. eventually you’ll come to the same conclusion as me. I can get the widest, fattest spark and gap at 50 thou + with a good ole Autolite 4264/5. Try that with the other brands… most fail miserably. This is also how I test coils by the way.
‘The type that don’t have anything to gap, your on your own. Still not a believer in them. Most run worse than a stock Autolite.
‘’Keep trying plug after plug and widening.. eventually you’ll come to the same conclusion as me. I can get the widest, fattest spark and gap at 50 thou + with a good ole Autolite 4264/5. Try that with the other brands… most fail miserably. This is also how I test coils by the way.
‘The type that don’t have anything to gap, your on your own. Still not a believer in them. Most run worse than a stock Autolite.
Last edited by Rains2much; Jan 26, 2026 at 08:06 AM.
Seasoned HDF Member
Joined: Jul 2014
Posts: 8,603
Likes: 3,374
From: Cental, MI
I am a zealot for 4264-4265 depending on heat range. I wanted to believe fancy spark plugs added magical power so I bought a number a few years ago. If you really wanna test them… Start opening the gap a little wider and then going full throttle. Keep widening until they cut out and then record the gap.
‘’Keep trying plug after plug and widening.. eventually you’ll come to the same conclusion as me. I can get the widest, fattest spark and gap at 50 thou + with a good ole Autolite 4264/5. Try that with the other brands… most fail miserably. This is also how I test coils by the way.
‘The type that don’t have anything to gap, your on your own. Still not a believer in them. Most run worse than a stock Autolite.
‘’Keep trying plug after plug and widening.. eventually you’ll come to the same conclusion as me. I can get the widest, fattest spark and gap at 50 thou + with a good ole Autolite 4264/5. Try that with the other brands… most fail miserably. This is also how I test coils by the way.
‘The type that don’t have anything to gap, your on your own. Still not a believer in them. Most run worse than a stock Autolite.
Last I knew stock did Not have removable cap... so, If yer stuff aint Stock...Might Not gonna Be OK..
Last edited by Racepres; Jan 26, 2026 at 08:49 AM.
Road Warrior
Joined: Feb 2018
Posts: 1,495
Likes: 1,158
From: Long Island
I remember needing plugs for my Ducati, dealer wanted something like $50 per plug, Champion w Ducati branding.
Looked up equivalent, bought Champion.
The Champion "equivalent" had a cap which I didn't't need.
Broke porcelain trying to remove the unremovable caps.
Went back to dealer, complained about price, he sold me a pair at approximately 40% discount.
Looked up equivalent, bought Champion.
The Champion "equivalent" had a cap which I didn't't need.
Broke porcelain trying to remove the unremovable caps.
Went back to dealer, complained about price, he sold me a pair at approximately 40% discount.
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HDF Community Team
Joined: Dec 2011
Posts: 8,589
Likes: 4,019
From: San Diego, CA
My old VWs used Bosch plugs, and you had to screw off the cap to use the VW plug boots. Perhaps you should buy a new set of plug wires that don't have a spark plug boot like my VWs? Taylor wires have boots that slip on the fully capped spark plug.
John
John
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Joined: Jun 2015
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From: West Central FL
Hello,
Could you please help in below two matters:
1. Are this the most used/best spark plugs for our EVOs? Are there any other brands/models that will fit?
Champion RN12YC
Autolite 4265
NGK BPR5ES
2. I need a spark plug with removable top nut, and have some hard times finding it..
Thanks
BR
Marcel
Could you please help in below two matters:
1. Are this the most used/best spark plugs for our EVOs? Are there any other brands/models that will fit?
Champion RN12YC
Autolite 4265
NGK BPR5ES
2. I need a spark plug with removable top nut, and have some hard times finding it..
Thanks
BR
Marcel
