I might splurge and buy a set of plugs for the Fronty R head.
Yes, I use them on my 1931 vintage Cragar OHV conversion. They are a hotter plug than the 3X.
About $7 each from O'Reilly's. I got mine from the Santa Ana store, but they can special order; takes about 4 or 5 days.
Thanks, Mike.
I checked www.RockAuto.com and they get $6 for the W18, but don't list a use for it. Here's what they have on the 1928-31 Ford:
-----------
AUTOLITE Part # 3076 Non Resistor
OE Style; Gap .032
$2.30
Nickel (extended service life without platinum enhancements)
MOTORCRAFT Part # SP465 Nickel
Gap: .032
$2.69
They don't list heat range or anything else. Is there a chart somewhere?
What follows is a posting by Larry Brumfield on Fordbarn REGARDING MODEL A spark plug heat ranges. I have used the TT10 (equivalent to 3076) before and it too cold IMHO. I believe, as do others, that the W18 is hotter than the W16Y.
HOTTER DOWN TO COLDER - Spark Plugs
For those who may be interested, the following 7/8"-18 spark plugs will fit the Model A and were available as of a few years back. They are also not all the ones that I know of.
Champion (hotter down to colder):
W95D
W89D
W16Y
W20
W18
W14
W10
W85N
W80N
Also the original 3X and W18 which Champion lists as norm. Also according to Champion, the W16Y is hotter than the W18 at low speed but cooler at high speeds over 5500 RPM.
Motorcraft (hotter down to colder):
TT15 (the same as Champion W89D)
TT10 (the same as Champion W14)
TT8 (the same as Champion W14)
TT4 (the same as Champion W10)
Autolite:
3076 (the same as Champion W14 and Motorcraft TT10)
Mopar (hotter down to colder):
P-9-7S
P-9-6S
P-9-5S
Prestolite (hotter down to colder)
78-10
78-8
Stitt (hotter down to colder)
137 BSP
197
147 B
13/10
Range is a key word when one speaks of heat range.
Reading these Champion numbers is not real difficult. For example, W20 or W18, etc.:
The W is the shell design and it always means 7/8-18.
I should also add that Champion has made changes over time. For example a C-16C, used in many a Model A, starts with a C, BUT it is a 7/8-18 plug. It was discontinued about 1979 and replaced by the W16Y. There are many like this.
The number is the heat range and the lower the cooler (unless other letters immediately follow, like Y for example, which depending on the letter or letters can change or affect the heat range):
1- 25 = Automotive and small engines
25 - 50 = Aviation
51 - 75 = High Performance
75 - 99 = Industrial and Special Applications
Larry B.
Last edited by Larry Brumfield; 06-30-2010 at 09:40 AM.
Thanks, Mike.
I wonder if any of the other Fronty guys looked at this, based on the incomplete title?
"Is Champion W18 a Model A Plug?
No, the W18 has a 3/4" reach and the Model A plug has a 5/8" reach.
Current production Champion plug for a Model A is a W16Y.
Original plug on a Model A was a 3X, then they changed to a C-4, then it was a C-16C before they changed again to the W16Y.
=========================================================================
This is a clarification that Larry Brumfield sent to me. Webmaster Chris
"Is Champion W18 a Model A Plug?
Yes, the Champion W-18 is most definitely a Model A plug and is a preferred choice for many Model Aers. Its 3/4” reach works just fine being that the original Champion 3X has a reach of 13/16”. Champion recommends the W-18 to be the modern replacement for the 3X as their heat ranges are fairly close. Concerning the W16Y, according to Champion, the W16Y is hotter than the W18 or even a W20 at low speed but cooler at high speeds over 5500 RPM... which obviously will never apply to most Model Aers.
However, most people report that the W16Y runs cooler than the W18 on a Model A at any speed. I doubt very seriously though that Champion’s engineers were using a Model A engine, as these plugs will work in several different engines, and their results would no doubt be determined under controlled conditions where the air/fuel ratio, spark intensity, etc., would be near perfect which is not the case for most Model A's. So it's still best to use the following as a general guide but do your own tests and reach your own conclusions and opinions when running these plugs in a Model A.
Champion (hotter down to colder)
W95D
W89D
W16Y
W20
W18
W14
W10
W85N
W80N
Also the original 3X which Champion lists as norm along with the W18.
Motorcraft (hotter down to colder):
TT15 (the same as Champion W89D)
TT10 (the same as Champion W14)
TT8 (the same as Champion W14)
TT4 (the same as Champion W10)
Autolite:
3076 (the same as Champion W14 and Motorcraft TT10)
Mopar (hotter down to colder):
P-9-7S
P-9-6S
P-9-5S
Prestolite (hotter down to colder)
78-10
78-8
Stitt (hotter down to colder)
137 BSP
197
147 B
13/10
Range is a key word when one speaks of heat range.
Reading these Champion numbers is not real difficult. For example, W20 or W18, etc.:
The W is the shell design and it always means 7/8-18.
I should also add that Champion has made changes over time. For example a C-16C, used in many a Model A, starts with a C, BUT it is a 7/8-18 plug. It was discontinued about 1979 and replaced by the W16Y. There are many that have been changed.
The number is the heat range and the lower the cooler (unless other letters immediately follow, like Y for example, which depending on the letter or letters can change or affect the heat range):
1- 25 = Automotive and small engines
25 - 50 = Aviation
51 - 75 = High Performance
75 - 99 = Industrial and Special Applications
(Message edited by adminchris on April 15, 2016)