Just removed the plugs a previous owner installed in my ‘76 stock 350. Those plugs were Champion RJ12YC, which are apparently a small engine plug. I replaced them with AC Delco Rapidfire #4. A much larger plug but recommended for this engine. Do any of you have any ideas as to why they had the Champions in there? Or what I might expect with the Delco’s? Not quite ready to fire it up yet. Thanks
CK5
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Spark Plug Questions
- Thread starter RJG
- Start date
Accel spark plugs, gap them to at least 35 or so
Outside of abnormal situations like a lot of oil getting into the cylinder and fouling plugs, the OEM Delco plug called for in that application is more than enough. Plugs aren't going to net you any difference on a stock engine, assuming everything was in good working order to start with, and you are putting proper replacements in.
Perhaps for a daily driver that gets a ton of miles on it the platinum type plugs could get you more time between changes, but for a low annual mileage rig standard cheap plugs (again of reputable manufacture) are fine.
Pretty sure most of the standard Delco's on mine (minus two or three I've broken) are 15-some years old. Lucky if they have 30K on them though, and the gaps haven't appreciably opened up every time I've checked. Not that gap makes a ton of difference either, again on a stock engine in good repair.
Perhaps for a daily driver that gets a ton of miles on it the platinum type plugs could get you more time between changes, but for a low annual mileage rig standard cheap plugs (again of reputable manufacture) are fine.
Pretty sure most of the standard Delco's on mine (minus two or three I've broken) are 15-some years old. Lucky if they have 30K on them though, and the gaps haven't appreciably opened up every time I've checked. Not that gap makes a ton of difference either, again on a stock engine in good repair.
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Thanks
Interesting, now I’m wondering he how long they’ve been in there.
Appreciate the input, this is definitely a low mileage truck. I’ll leave these Delco’s in and see what happens.
Champion = fishing weight
I’ll chime in, I don’t think Delcos are what they used to be, my last set of 45s was junk….I’ve been using the accels and NGKs. I do run champions in my Mopars but that was OEM and they seem to do well with them.
