Spark plug conversions - 1
Spark plug conversions
Spark plug conversion table
Spark Plug List
Application notes provided by Don Roubos |
|
Application
|
New Champion
|
Old Champion
|
A--C
|
Auto Lite
|
|
4-cyl
|
C-26(c)
|
C-4
|
76-S(7/8"Hex)
78-S(1 1/8" Hex)
|
|
The heat range is not as important an issue as the fact of about 1/2" of metal reaches below the end of the threads. The DB's combustion chamber is configured such, that the spark plugs are up in a recess, and a 'normal' plug will carbon up after the first tour. A longer plug gets the spark closer to the actual combustion area.
Roger "Dodger" Hartley
7/8" spark plugs cold down to hot
|
Application
|
New Champion
|
Old Champion
|
A--C
|
Auto Lite
|
|
|
W-10
|
0 Com
|
73 Com
|
|
|
|
W-14
|
1 Com
|
74 Com
|
T-7
|
|
6-cyl Victory & Senior thru 1928
|
W-18 (#518)
|
2 Com
|
C 77L
|
T-9
|
|
|
W-20
|
3 Com or No 20
|
78 Com
|
T-11
|
|
|
W-89D
|
44
|
18
|
3077
|
|
|
W-85N
|
901
|
|
|
|
|
W-95D
|
45
|
|
|
The bottom three plugs are special extension models
Recommended torque for a cast iron head is 37 lb-ft
35 lb-ft for aluminum
10 mm cold down to hot
|
Application
|
New Champion
|
Old Champion
|
A--C
|
Auto Lite
|
|
|
UY-6
|
Y-4A
|
104
|
P-4
|
|
|
UY-6
|
Y-6
|
106
|
|
|
|
UY-6
|
Y-8
|
108
|
P-6
|
Recommended torque for cast iron head is 14 lb-ft
12 lb-ft for aluminum
14 mm cold down to hot
|
Application
|
New Champion
|
Old Champion
|
A--C
|
Auto Lite
|
|
|
J-57-R
|
J-2
|
42
|
A3
|
|
|
H-8
|
H-9
|
43L
|
A5
|
|
1932-1942 Aluminum head
|
CJ-8 (#841)
|
J-8
|
45
|
A7
|
|
|
UJ-12
|
J-12
|
47
|
A11
|
Recommended torque is 30 lb-ft for cast iron heads
28 lb-ft for aluminum
18 mm cold down to hot
|
Application
|
New Champion
|
Old Champion
|
A--C
|
Auto Lite
|
|
|
D-6
|
4 Com
|
82S
|
|
|
|
D-9
|
5 Com
|
83-S
|
B5
|
|
|
D-14
|
6 Com
|
84
|
B7
|
|
1929 6cyl 1930-31 6 & 8 cyl
|
D-16 (#516)
|
7
|
85-S
|
|
|
1929 6cyl 1930-31 6 & 8 cyl
|
D-16 (#516)
|
8 Com
|
86
|
B9
|
|
|
D-21
|
C-15
|
87
|
B11
|
|
|
D-23
|
10 Com
|
88-L
|
388
|
|
|
D-89D
|
49
|
18A
|
|
The bottom plug is a special extension model
Recommended torque for cast iron is 34 lb-ft 32 lb-ft
for aluminum heads
For 1/2" pipe plugs recommended torque in cast iron
is 35 lb-ft
All values are for clean lubricate threads.
Over tightening a plug with a .025 gap the gap will
increase to .031.
Created from a 1947 heat range list and current Champion
list.
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