hanktohendrix

In my L76 I'm using the original AC Delco 44.
I guess the 44 are a bit too cold.
In stock I have new AC Delco 7.
Nothing more written on it, just 7.

Is that #7 the new heat range declaration? Compareable with the old Delco 44, or NGK or Bosch?

Thanks!
Markus

Frankie the Fink

44 is way too cold ... a good replacement that you should find over there is NGK-XR4. I run them in my '61 and '63 small blocks...

AZDoug

Or an AC 45, which was the normal street plug choice

Doug

Plasticman

http://parts-catalog.acdelco.com/cat...&parttype=3210

Above list (click on Chevrolet, and then Corvette). It lists used from 1965 through 1970 on 327 & 350 engines.

Here is a cross ref. list:

Replacement spark plugs for AC DELCO 7:

Autolite AP85
Autolite AP847
Autolite AP86
Bosch WR9FPZ
Bosch WR9FPY
Champion RJ18YC6
Champion stk 66
Denso W16PR-U15
Denso stk 3038
General Motors 25171346
General Motors 5613591
Mighty M4R426
Mopar 4339428
Motorcraft AS42C-6
Motorcraft stk 17
NGK XR4VX
NGK XR45VX
NGK stk 2292
NGK stk 3348
Prestolite 14-32
Splitfire SF008E
Splitfire SF008G6
Splitfire SF008E6
Splitfire SM008E
Valley Forge 144R

I cross ref. the above Champion RJ18YC6, and got the following list (which includes AC R44SX, R45SX, R45TS8, and R46 various plugs, and R47SX):

Replacement spark plugs for Champion RJ18YC6:

AC Delco R45TS8
AC Delco R46SZ
AC Delco R44SX
AC Delco R45SX
AC Delco R46SX
AC Delco R46S
AC Delco R47SX
AC Delco 7
Accel 198
Autolite 3547
Autolite 566
Autolite 567
Autolite 966
Autolite 3647
Autolite AP847
Autolite 847
Autolite 565
Beck Arnley 176-5191
Bosch WR10FCZ
Bosch WR9FPY
Bosch WR10FCY
Bosch WR9FCY
Bosch WR11F
Bosch HR10BCZ
Bosch stk 7517
Champion RJ18YC8
Champion RJ18Y8
Champion RJ18Y6
Champion stk 66
Denso W9PR-U15
Denso W16PRU15
Denso W9PRU
Denso W9PRU20
Denso W16PR-U15
Denso W9PR-U
Denso W9PR-U20
Denso W9PRU15
Denso W14PR-U15
Denso stk 3038
Denso stk 5043
General Motors 5613721
General Motors 5613564
General Motors 5613882
General Motors 5613591
General Motors 5613881
Mighty M4R426
Mighty M4R826
Mopar 4339428
Motorcraft ASF52C-7
Motorcraft AR82-6
Motorcraft AS82-7
Motorcraft AR82
Motorcraft AS42C-6
Motorcraft AR82-8
Motorcraft stk 17
Motorcraft stk 26
NGK XR45IX
NGK XR45
NGK BPR4S-20
NGK BPR4S-15
NGK XR45VX
NGK stk 4536
NGK stk 3348
Valley Forge 144R
Valley Forge 216R
Valley Forge 148R


Plasticman

hanktohendrix

Thanks a lot guys!
That list is very helpful for me, plasticman
So the AC Delco 7 (next to me on the desk) are equal to Delco 45 or NGK XR4 I want to get

Markus

Plasticman

Note that the AC Delco 7 appears to be an extended tip plug (same tip configuration as the old R45S - the "R" is for "resistor", while the "S" is for the extended tip).

Both they, and the NGK XR4 are resistor plugs (I never saw the purpose of running both resistor wires and resistor plugs).

Here is the cross ref. for the AC Delco R45S (the NGK XR4 is listed):


AC DELCO R45S - Alternative spark plugs
Replacement spark plugs for AC DELCO R45S:

Accel 0437S
Accel 138
Accel 0437
Autolite 86
Autolite AP86
Autolite AP85
Beru 14R-11F
Bosch WR9FP
Bosch WR10FC
Bosch WR10F
Bosch WR9FC
Bosch stk 7519
Champion RJ18YC
Champion RJ12YC
Champion stk 58
Denso W14PR-U
Denso W14PRU
Denso stk 6021
General Motors 5613872
Mighty M4R52
Motorcraft AR52
Motorcraft AS52C
Motorcraft stk 57
NGK XR5VX
NGK BP5S
NGK XR4VX
NGK XR4
NGK stk 2292
NGK stk 5858
NGK stk 5485
Splitfire SF008E
Torch G5TC
Valley Forge 45R

Here is the cross ref. list for NGK XR4

NGK XR4 - Alternative spark plugs
Replacement spark plugs for NGK XR4:

AC Delco R45S
AC Delco R46S
AC Delco R44S
AC Delco 46S
AC Delco R47S
Accel 437
Accel 0437S
Accel 138
Accel 0437
Autolite 77
Autolite 87
Autolite 565
Autolite 86
Bosch WR8FC
Bosch WR10FC
Bosch stk 7519
Champion RJ14YC
Champion RJ14CC
Champion OJ11Y
Champion RJ18YC
Champion stk 58
Champion stk 63
Denso W16PR-U
Denso W16PRU
Denso W9P-U
Denso W14PR-U
Denso W9PR-U
Denso stk 6006
Denso stk 6021
Denso stk 6007
General Motors 5612390
General Motors 5613879
General Motors 5613872
General Motors 5613115
Mighty M4R52
Mopar 2444870
Motorcraft AR42
Motorcraft AS52C
Motorcraft stk 57
Napa X904
NGK stk 5858
Prestolite 14-82
Splitfire SM008E
Valley Forge 45R

And here is the list for AC Delco 45:


AC DELCO 45 - Alternative spark plugs
Replacement spark plugs for AC DELCO 45:

Accel 124
Autolite 295
Autolite 316
Beru 14-8E
Beru 14-10E
Bosch W8E
Bosch W10EC
Bosch W9EC
Bosch WR9EC
Bosch stk 7515
Brisk K17C
Brisk K19
Champion J8C
Champion RJ12C
Champion UJ12C
Champion J12C
Champion J8
Champion J8J
Champion UJ12
Champion J11C
Champion stk 511
Champion stk 841
Denso W14US
Denso W14-U
Denso W16SU
Denso stk 6008
Eyquem FS30
General Motors 1559493
Iskra FS30
Iskra FS50
Lodge BAN
Mopar 4339491
Motorcraft A7
Motorcraft AS8
Motorcraft A5
Motorcraft stk 77
NGK B4
NGK 3210
NGK stk 3210
Prestolite 14-07-01
Splitfire SM029E
Torch G4C

Plasticman

Bill Pilon

AC 7 is part of the AC rapid fire series, they were the "thing" before the platinum plugs became common place.