The same ones the factory used.
The factory Champions. RC12LYC I think.
platinum plugs atleast that's what they come with from the factory
It is best to go with the factory used spark plugs. The factory uses champions.
Champion rc12lyc
i may not b the best at that subject but i plugs into the transmissin pretty much
It would be best to use the newer platinum plugs bosch makes a good plug It would be best to use the newer platinum plugs bosch makes a good plug
The rear 3 plugs are almost inaccessible, the BOTTOM LINE is that you would need to actually drop the rear on the engine and use of a "cradle" to tackle the removal and installation of spark plugs. The metal AIR plenum at the rear of the engine is insulated and there is NOT ENOUGH room to access and work in the rear bay. My best advice is to unfotunately, take it to a shop or the Dodge Dealer. It will rance from 150-300 dollars for mopar plugs and labor.
AC/DELCO is the best brand. Just get whatever specifications meet your car.
Best way to diagnose is to scan for codes, but not having that I would guess the ignition module then the crank/cam sensor.
My best guess would be the plugs aren't igniting the fuel and it's collecting on the plug.
NGK V-Power Spark Plugs are a great fit for the 1970 Dart 340, so I would definitely recommend those. Hope this helps -Rich
Champion SPRE14MCC4. Those are the stock and work just great.