Best spark plugs for a slant 6 225

['64 Belvedere]

I have a '64 Belvedere with 225 slant 6. What are the best plugs to run in this. I am slowly upgrading to an electronic ignition. I have a blaster2 coil and msd 8.5 wires and a msd 6200 is next. Anyone have any thoughts.

[JVMopar]

Personally I like Champions.

I had a '78 Volare /6 and tried some autolites. It wouldn't hardly run so I just regapped the NGK's that were in there and put them back in. So I would stay away from them.

If you want to use a precious metal plug you only need a single platinum plug. Save some bucks cause you'll get no benifit from double platinum's.

['64 Belvedere]

I just had two other guys tell me they liked the NGKs from another Mopar chat. What didn't you like about them. I know you said you had to regap them but after how long? I like as much info as poss and thanks for the post.

[Ray Bell]

It was the NGKs he continued using, Autolites he bagged...

Just out of curiosity, what trans do you have in that car?

[JVMopar]

Yup just like Ray said. The NGK's were in the car when I got it. I put in some autolites and it wouldn't run worth a damn. So I regapped the NGK's and put them back in and threw the autolites away. I've been using Champions on everything I own, but I don't own that /6 anymore.

[old woolie]

Champions for me as well.

[Rug_Trucker]

Originally Posted by '64 Belvedere

I have a '64 Belvedere with 225 slant 6. What are the best plugs to run in this. I am slowly upgrading to an electronic ignition. I have a blaster2 coil and msd 8.5 wires and a msd 6200 is next. Anyone have any thoughts.

Going electronic you will need to upgrade the charging system. Not to steal any thunder from this site......there is a slant specific website.

Some do a GM HEI conversion. I am considering that for my Duster.

[Rug_Trucker]

I always had good luck with Autolites. Now are made in China. I switched to NGK.

[Coldrold52]

I read up on some actual research back awhile and the study showed that autolite worked best in a nice clean-burning low milage motor. It lasted longer. champion worked best in the higher milage motor. It didn't last quite as long but the "kernal" of spark was a little larger thus causing quicker erosion of the electrode but a better running older motor. Now there are lots of other "claims" on the board but I haven't read or heard any where that there is any major breakthroughs. Most of the newer ones are around because the big three had to have a plug that would last 100k. [no tune-ups in warrenty period].

[Rug_Trucker]

There has been some QC issues with the Autolites. It has been a while pics were hilarious.