Spark plug cross over sheet.

[wolf]

Here are some spark plug cross over part numbers:

Plug Manufacturer TC88/95 Engine
Plug Gap .040"
H-D Standard 6R12
H-D Gold 6R12G
H-D Platinum 6R12PP
Champion RA8HC
Autolite 4164
Autolite Platinum AP4164DP2
ACCEL 2418
Y2418P
Splitfire SF416D
Screamin Eagle EX12S
EX12P
ACDelco
NGK DCPR7E
Bosch
Denso Iridium
IXU22

Spark Plugs for
80 CID Evolution Engine
Plug Manufacturer 80 CID Evolution 1984-up
Plug Gap .040"
H-D Standard 5R6A
H-D Gold 5R6AG
H-D Platinum 5R6APP
Champion RN12YC
Autolite 4265
Autolite Platinum AP4265DP2
ACCEL 2410A
Splitfire SF6D
Screamin Eagle EVS13S - Hot
EVS13P - Cold
ACDelco 44NS
NGK BPR5ES-11
NGK Platinum BPR5EVX-11
Bosch WR8D
WR8DC
WR8DP
Denso Iridium IW16

Spark Plugs for
Sportster Engines
Plug Manufacturer Sportster 86-up
Evolution Engine Sportster 80-85 Sportster 72-79
Plug Gap .040" .040" .040"
H-D Standard 6R12 4R5 4-5
H-D Gold 6R12G 4R5G 4R5G
H-D Platinum 6R12PP
Champion RA8HC RL82YC H8C
Autolite 4164 4123 996
Autolite Platinum AP4164DP2
ACCEL 2418
Y2418P 2413 2402
Splitfire SF416D SF21F SF21F
Screamin Eagle EX12S
EX12P XL10S XL10S
ACDelco
NGK DCPR7E
Bosch
Denso Iridium IWU22
IX24B IWF22

Spark Plugs for
Shovelhead Engines
Plug Manufacturer Shovelhead 82-84 Shovelhead 80-81 Shovelhead 78-79 Shovelhead 75-80
Plug Gap .040" .040" .040" .040"
H-D Standard 5RL 5R6A 5A6A 5R6A
H-D Gold 5R6AG 5R6AG 5R6AG 5R6AG
H-D Platinum 5R6APP 5R6APP 5R6APP 5R6APP
Champion RN13LYC RN12YC N12YC RN12YC
Autolite 2585 4265 4265 4265
Autolite Platinum AP4265DP2 AP4265DP2 AP4265DP2
ACCEL 2417 2410A 2403A 2410A
Splitfire SF426E
TP6E SF6D SF6D SF6D
Screamin Eagle EVS13S - Hot
EVS13P - Cold EVS13S - Hot
EVS13P - Cold EVS13S - Hot
EVS13P - Cold EVS13S - Hot
EVS13P - Cold
ACDelco
NGK ZGR5C-11
BPR5ES-11 BPR5ES-11 BPR5ES-11
NGK Platinum BPR5EVX-11 BPR5EVX-11 BPR5EVX-11
Bosch

[Dave]

i can add to this a simple method of choosing plugs from an auto parts store.. if you have the larger plug in a shovel or evo.. any parts store will have a autolite 65 or ap65 .. i prefer the ap65 personally..

on twin cams , sporty's & other aftermarket evo. motors , using the plug with a small wrench head the autolite 4164 is readily available ..

i prefer the autolite over all others.. that just me, but they do work well .. i atually called allied signal .. the makers of auto lite .. i asked what the difference was in the bike & auto grade plugs.. there is no difference function wise.. the auto versions for the most part have a black wrench head o them.. while the bike grade has a silver .. otherwise they are identical plugs.. this refers to the standard plug, not the fine wire type.. but then being hard set in mmy thinking, the standard type plug is all i use.. this cross reference wolf added is very good info.. as you could get stuck in a pinch & need to know what will actually work in your bike..

[xylene61]

I just pulled the plugs outta "Blossom'. They were Champion RN14YC. I stuffed in a new set of RN12YC, as per the handy crossover in this forum. Anybody know the difference in these plugs? Why did I have the 14's in it? hotter/colder? What would be my advantage over stock? I looked at the Champion website, but no answers there.

[xylene61]

oh, yeah, Blossom runs an 80 evo with wee bit bigger 10:1 screamin' beagle pistons, EV46 cam, mikuni 42, crane hi4 & stainless duals. It gets Sunoco 94 to quench that thirst.
The RN14Y's looked good comin' out, with nice colour on the back, and some traces of soot on the front.

[wolf]

Xylene61 Here Brother is all you would ever want to know about spark plugs long reading but some good information. go through all the pages the last will show plug readings.
http://www.centuryperformance.com/spark-plug-tech-spg-26.html