spark plug number

[38plymouth]

I am in the middle of swapping my stock head back onto my 38 Plymouth 201. I checked my manual and tried to search online with my phone but I'm still not getting a positive answer. I don't think the search function on this forum works well with a phone. Is AC 45 the correct plug number? I do have a split exhaust manifold and dual exhaust and live in Florida if that makes a difference for the heat range.

[Don Coatney]

AC R45 is what I use.

 

The difference in a hot and cold plug is simply the distance the electrode is from the water jacket.

 

[38plymouth]

Thank you

[deathbound]

I was running Autolite 295 (same as AC 45 in the x-reference) with the stock head in my '38 Plymouth 201 c.i. with good results.

[greg g]

I have Ac 46 in mine no issues in 30 K miles on the same set now that I think about it.  Still running fine,

[ellum]

HI guys,

 

Anything bad in using Champion J8C? Or are the AC 45 better?

 

Thanks

Elvis

[Don Coatney]

Personally I have had more failures with Champion plugs than any other brand.

[Jerry Roberts]

I also had problems with Champion plugs , I took them out and threw them away . It seemed like they were leaking the compression out , perhaps between the steel and the porcelain .  

[Robert Horne]

• I have been running J8 Champions for many years, no problem.    

[Niel Hoback]

  I am using Chryco CP-1.  They work great even though I have no idea what the heat range is.

[1941Rick]

I ran NGK with poor results. Now run Champion with no trouble at all....guess you can get duds with anything.....