what plugs did 2nd run cars come with?

[etfhb]

22's or 32's

will autolite ar103's work fine as a replacement plug for a stock pully cobra, if no any suggestions.

i had my car on the dyno last week and the tuner suggested ar103's for a stock cobra

i read somewhere that the 103's were 1 heat range colder then stock plugs, but what plug 12, 22, or 32.

 

[ShelbyGuy]

mine came with 22s

ar103 should work fine.

ideally you want the coldest plug that doesnt foul and the widest gap that doesnt blow out.

 

[CobraBob]

I would just pull a plug and check. They're very easy to get at. The three plugs that came from the factory were AGSF12FM1, AGSF22FM1 & AGSF32FM1. The '12s' were the first run. The 22s were mid year (I know JB had these and his was made in September). The 32s were the last runs. However, I don't specifically which production dates used which plugs. You could have either the 22 or 32. The first plug is a colder than the other two. Personally I would go with the NGK TR6 plugs for your car.
:

 

[1BDSNK]

I'm using the APP103's which are the Plantinum version of the AR103 and they work just fine.

 

[JB]

generally, platinum plugs aren't well-suited to forced induction applications

Ford only used them to lengthen service intervals

.

 

[TEABG]

mine came with 22s

ar103 should work fine.

ideally you want the coldest plug that doesnt foul and the widest gap that doesnt blow out.

AR103 suck Donkey Dick!!!!!!! NGK TR6 IX :thumbsup: First run Cobra's came with the 12's which are NGK TR7 heat range.

 

[1BDSNK]

generally, platinum plugs aren't well-suited to forced induction applications

Ford only used them to lengthen service intervals

.

JB,

I wasn’t aware of that, thanks for the info. The APP version is more expensive anyway. I originally intended to purchase the AR’s instead of the APP, but up here in Lapeer all I could find on the shelf at the auto parts stores were the APP and the AR’s were special order. I even had a hard time finding a full set of eight.

Take care.

 

[FireRed04Vert]

The thing to remember is a plug's heat range has absolutely nothing to do with how hot the plug burns. That's pretty constant across the board. What a heat range refers to is the plugs ability to transfer heat out of the combustion chamber.

A TR6 is a hotter plug than a TR7.

This is a good read. I recommend it to help clear up any confusion.

http://www.ngksparkplugs.com/techinfo/spark_plugs/overviewp2.asp?nav=31000&country=US

 

[etfhb]

it's always nice to hear suggestions from a few of the heavy hitters:beer:

i'm leaning towards a copper plug @ the same heat range as the "22s" so exactly what you suggested CobraBob: NGK TR6 seems to be right on, as well as the copper autolite ar103.

FireRed04Vert, thanks for the link, it had some useful info.

 

[FireRed04Vert]

You're welcome!