3X plugs - Wow!

Does anyone really think that the 3X design adds some AMAZING performance gain to A Model A, or is it just for looks? Bill W.

Could it be that the 3x plugs are just hotter then the motorcraft and any hotter pug would have given better results?

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....(over 5500 RPM? ... maybe Speedy ED J, Pete, George Miller, Dennis Pierce would be interested... maybe even Brent)

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.
 
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Clean new plugs properly gapped run better than used but not necessarily worn out. One time while dyno testing a 409 we put new plugs of same manufacture in, and showed a 6hp gain.
 
Mike, where did you get your Champion hotter down to colder list?? Here is how that I see it
W95D
W89D
W20
W18
W16Y
W14
W10
The Champion heat range list doesn't show 3X . It lists W18 at a heat range of 7 and the W16Y at a heat range of 6 . I've been told that the W16Y gets hotter at 5500 RPM The extended electrode on the W16Y is a misnomer for being hotter on the model A because most model A's are incapable of turning 5500 RPMs I'm not saying this for the sake of argument. I once got banned for three months for pointing this out. Anybody that has used W18 spark plugs will tell you that they are noticeablely hotter than the W16Y.
 
Mike, where did you get your Champion hotter down to colder list?? Here is how that I see it
W95D
W89D
W20
W18
W16Y
W14
W10
The Champion heat range list doesn't show 3X . It lists W18 at a heat range of 7 and the W16Y at a heat range of 6 . I've been told that the W16Y gets hotter at 5500 RPM The extended electrode on the W16Y is a misnomer for being hotter on the model A because most model A's are incapable of turning 5500 RPMs I'm not saying this for the sake of argument. I once got banned for three months for pointing this out. Anybody that has used W18 spark plugs will tell you that they are noticeablely hotter than the W16Y.

Larry Brumfield
 
Ordered mine yesterday, picked them up this morning! Look great! I plan on putting them in this evening, will post if there is any change in how the car runs!
 
Dog:cool: here,
A friend got sum 3X's & said the wire thingys wur bent sum. When he straightend them, they were too short & it wuz hard to set the gap??
Vermin's got brand new Champion C-16-C's & Ol' Bill sed they fit sum old Packards too! Is he pullin' my legs? Buster T.:cool:
 

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I will clarify my last post, my wife an I just went for a 40 min drive around town and I think it did run better. But it's still prettier. Lol!
 
I have to agree with Purdy, the W18 is defintely hotter than the W16. Absolutely no doubt about it. I recall Larry B posting this information, which is very informative, and noticing that he lists the W16 as hotter than the W18. But I have only gotten my Model A engine to turn 5400 rpms, not 5500, so my tests may be inconclusive.:)
 
I got 'em too and my sedan delivery now goes REAL fast and smooth and doesn't burn gas... well almost. Ordered them July 3rd; was told they'd be in on the 9th; they called on the 7th... they were in. Happy camper, so's my A!
 
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