CRG Discussion Forum

Camaro Research Group Discussion => Maintenance => Topic started by: marriest on March 05, 2020, 04:08:31 PM

Title: Spark plugs for 396 / 325 hp
Post by: marriest on March 05, 2020, 04:08:31 PM

What kind of plugs should be in a 1969 Camaro BB Pace Car RS/SS 396/325 Hp. It has AC Delco R43 xls in it but the Owners manual says R43 N.
What is recommended?
Terry

Title: Re: Spark plugs for 396 / 325 hp
Post by: bertfam on March 05, 2020, 04:36:10 PM

Terry, I moved your thread to Maintenance, but if you have a "show car", then you'll need to spend the big bucks on the ORIGINIAL "GREEN RING" R43N PLUGS (https://www.ebay.com/itm/AC-Acniter-Spark-Plugs-Chevrolet-396-427-R43N/303505004944?epid=1923074879&hash=item46aa4ed990:g:pEUAAOSw6DNcYd68). If not, then I like Autolite and AC Delco. I stay away from Champion since they just don't last.

Ed

Title: Re: Spark plugs for 396 / 325 hp
Post by: marriest on March 05, 2020, 05:40:34 PM

What is the difference btw  R 43N & R 43 xls

Title: Re: Spark plugs for 396 / 325 hp
Post by: bertfam on March 05, 2020, 05:46:07 PM

I don't believe there's any difference performance wise. The XLS is just the latest version that's being sold. More info on Delco numbering system HERE (https://www.sparkplugs.com/Data/uploads/Charts/ac%20numbering%20system.jpg).

Ed

Title: Re: Spark plugs for 396 / 325 hp
Post by: Mike S on March 05, 2020, 06:03:44 PM

The XLS allows the gap to reach a little further into the chamber. I run those mainly.

Mike

Title: Re: Spark plugs for 396 / 325 hp
Post by: adjudimo on March 07, 2020, 12:28:40 PM

The XLS is what I use to run in a 396/325. And I agree with Ed. Stay away from the Champion's.

Title: Re: Spark plugs for 396 / 325 hp
Post by: 1stgen68 on July 15, 2020, 02:40:46 PM

I run R44XL's in my 396 gapped at .40

Title: Re: Spark plugs for 396 / 325 hp
Post by: ko-lek-tor on July 17, 2020, 01:05:32 PM

Little off topic. I have heard the best plug is NGK. I can’t seem to find a number to cross over though?

Title: Re: Spark plugs for 396 / 325 hp
Post by: 169INDY on July 17, 2020, 06:15:24 PM

396/325 68
NGK Stock No. 2635
G R 4

Title: Re: Spark plugs for 396 / 325 hp
Post by: ko-lek-tor on July 19, 2020, 10:53:28 AM

Quote from: 169INDY on July 17, 2020, 06:15:24 PM

396/325 68
NGK Stock No. 2635
G R 4

Thanks!

Title: Re: Spark plugs for 396 / 325 hp
Post by: Charley PHX on November 17, 2022, 08:07:15 PM

Couldn't find the chart linked in #3 above (2020 post)... So I went looking for the document & found it (I think?)...

Updated link (AC/Delco numbering system):  https://assets.sparkplugs.com/lc/ac%20numbering%20system.jpg 

The host site appears to be kind-of a "Spark Plug University" of sorts... Connoisseurs can just go plumb crazy at:  https://www.sparkplugs.com/

Here's another link to multi-manufacturer data:   https://www.sparkplugs.com/learning-center/5-charts-tools

I'll open a new thread with this reference info. under a more general subject heading. ( http://www.camaros.org/forum/index.php?topic=20356.0 )
Moderators, pls. edit subject title and/or move as deemed appropriate?

ENJOY...

Title: Re: Spark plugs for 396 / 325 hp
Post by: HOGDADDY on November 17, 2022, 11:24:47 PM

I have been running Champion plugs (RC-12YC) in my Edelbrock RPM heads per their recommendation for years and never had any problems.
They are 1/4 " shorter for header clearance also.

I just replaced a set and probably wasted my money. The plugs looked ok. They were pretty old.