Shorty spark plugs
Thread Starter
Cruising
Joined: Jun 2011
Posts: 13
Likes: 0
From: Taneytown MD
Shorty spark plugs
I'm having an problem with my plug boots melting do to the hooker side headers. I'm looking for a short spark plug for a 427, anyone know of any. The stock plug is a AC Delco R44xls.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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You can get them from Accel and others, but truthfully if you go the parts store or look on line you can usuallu cross reference a regular plug to one fo the shorter ones. They are common in some Japanese cars..that's where they really come from. Just look up your threads and length, seat style, heat range etc and you'll be able to get a set locally.
BBC usually aren't too bad on wires and headers. Maybe a set of heat boots/sleeves would help?
JIM
BBC usually aren't too bad on wires and headers. Maybe a set of heat boots/sleeves would help?
JIM
Pro
Joined: Apr 2004
Posts: 621
Likes: 37
From: Texas
Easy money....
Easy....
Champion RC12YC Very common plug at most parts stores
I have done tons of spark plug research over the years and have found alot of shorty plugs that are just plain common plugs. never buy a high dollar plug just because it is a shorty or so called "header plug"
Champion RC12YC Very common plug at most parts stores
I have done tons of spark plug research over the years and have found alot of shorty plugs that are just plain common plugs. never buy a high dollar plug just because it is a shorty or so called "header plug"
Race Director
Joined: Apr 2000
Posts: 17,646
Likes: 189
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Easy....
Champion RC12YC Very common plug at most parts stores
I have done tons of spark plug research over the years and have found alot of shorty plugs that are just plain common plugs. never buy a high dollar plug just because it is a shorty or so called "header plug"
Champion RC12YC Very common plug at most parts stores
I have done tons of spark plug research over the years and have found alot of shorty plugs that are just plain common plugs. never buy a high dollar plug just because it is a shorty or so called "header plug"
Melting Slicks
Joined: Nov 2005
Posts: 3,322
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From: Green Valley Arizona
LannyL81
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Advanced
Joined: Jul 2008
Posts: 87
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From: Hokksund, Norway
(Note: For SBC alu heads)
Cold
NGK BCPR6EY-11 (equals 3923 and RC9YC4)
Autolite 5224 (equals RC11ZYCA and ZFR5E-11)
Champion RC12YC 71 (equals 3926 and BKR4E)
Hot
If you look at the pic, the NGK is longer than the Autolite and the Champion.
The NGK has a very close fit under the PATRIOT Tight Tuck Ceramic Coated from Corvette Central. Both the Autolite and the Champion fit perfect.
Arne
Cold
NGK BCPR6EY-11 (equals 3923 and RC9YC4)
Autolite 5224 (equals RC11ZYCA and ZFR5E-11)
Champion RC12YC 71 (equals 3926 and BKR4E)
Hot
If you look at the pic, the NGK is longer than the Autolite and the Champion.
The NGK has a very close fit under the PATRIOT Tight Tuck Ceramic Coated from Corvette Central. Both the Autolite and the Champion fit perfect.
Arne
Last edited by arneoe; Aug 19, 2011 at 05:16 PM.
Drifting
Joined: Jul 2004
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From: Kissimmee fl
Finalist 2021 C3 of the Year - Modified
2017 C3 of Year Finalist
Cruise-In VIII Veteran
St. Jude Donor '07
All of the plugs shown seem to have the compression washers. If you were running the later style cast iron heads and using the plugs with the 5/8 hex, tapered seat plug, what will the crossover plug be to go shortie? Thanks
Pro
Joined: Apr 2004
Posts: 621
Likes: 37
From: Texas
take your pic. long or short thread. all shortys on top
from left to right
champion v59yc,ngk br6fs,autolite 103,ngk tr55
the br6fs is a not projected tip
heat ranges are close but final tuning is up to you.
from left to right
champion v59yc,ngk br6fs,autolite 103,ngk tr55
the br6fs is a not projected tip
heat ranges are close but final tuning is up to you.
Last edited by project C4; May 6, 2015 at 07:38 PM.
Thanks. 
Drifting
Joined: Jul 2004
Posts: 1,695
Likes: 64
From: Kissimmee fl
Finalist 2021 C3 of the Year - Modified
2017 C3 of Year Finalist
Cruise-In VIII Veteran
St. Jude Donor '07
Even the Shorty plugs listed by Summit, made by Accel, describe them as being only 1/4 to 3/8 in. shorter than standard plugs. Thanks again C4 for the info. 
Thread Starter
Cruising
Joined: Jun 2011
Posts: 13
Likes: 0
From: Taneytown MD
I may have fix my own problem. I cut the melted boot off, wrapped some non-metal insulation around the bare plug terminal, then I had some shrink tube I got with plug wires and put two shrink tubes. I haven't driven yet, but I started the car up and have no arcing and the engine ran smooth. The shrink tube has to be heated with a butane lighter or torch so I'm hoping this will work, looks like hell but that's the breaks.
Thread Starter
Cruising
Joined: Jun 2011
Posts: 13
Likes: 0
From: Taneytown MD
I ordered a set of Accel ceramics, but I'm still looking for a short spark plug, not the threads, I need it shorter from the seat to the electrode. I have to find a Champion RC12YC and take a look. Again this is for a 427, AC Delco R44XLS are what in it now. Thanks