389 spark plugs

[64 kiwi boni]

hi guys, where do i find the info on what spark plugs to run in my  1964  389 4 barrel powered Pontiac 🙄

AND... what brand works best... i personally have had a good run out of ngk and a really bad run out of champion !!X😡

[Frosty]

Hi Kiwi - Here is a short list of plugs in no particular order or regard to price.

Platinum Tipped

Bosch 4236  gap .030

Autolite AP86   gap .035

AC Delco 7   gap .035

 

Copper

Autolite 86 Resister  gap .035

DENSO 6021  gap .027

AC Delco R45S  gap.035

CHAMPION 63 {#RJ14YC} Copper Plus   gap .035

NGK 5858 {#XR4} V-Power  gap .035

Double Platinum

AC Delco 41833   gap .035

Iridium

NGK 7189 {#2292, XR4IX} Iridium IX   gap .035

 

I run AC Delco, but I readily admit that I am bias towards them because I use to work for AC Spark Plug Division of GM when I first started working. I buy new old stock plugs and oil filters for all my Pontiacs at swap meets that were made in Flint Michigan. I tried E3 plugs on my '04 Avalanche. I thought they were a waste of money. I am fond of NGKs when I had personal watercrafts. I run Champion plugs in my lawn mowers and snowblower. The modern vehicles all run OEM AC Delco/NGK plugs - platinum or iridium, depending on what is OEM.

That said, for an AC plug I'd run the R45S plug. It's the lowest cost plug since I doubt you will be driving it like a daily driver, you are not going to rack up a ton of miles on it. Obviously, you can stick with NGK as well.

Edited January 29, 2021 by Frosty

[JUSTA6]

16 hours ago, 64 kiwi boni said:

hi guys, where do i find the info on what spark plugs to run in my  1964  389 4 barrel powered Pontiac 🙄

AND... what brand works best... i personally have had a good run out of ngk and a really bad run out of champion !!X😡

AC Delco runs best in my 421.  Champion.....not so much.  NKG???? Fine for my Jap dirt bikes, snowmobiles, never ran one in a car. Champion seems to run best in my small engines. Go figure.   Very interested in E3 plugs.  Believe they are made in FLA.  Have heard great things about them but they are pricey.