Smooth engine operation

Pros: Does give your engine a performance boost, hands down

The engine runs more rough than before

Engine ran well but my mileage dropped

Going back to the NGK plugs before my engine is damaged.

I installed these plugs in 2005 dodge ram pickup, the engine runs smooth as silk and gas mileage has improved.

Nothing wrong with NGKs,They just max out when the engine is old, so you have to look else where to enhance an old engine, like mine.

After a few hours of use the engine became hard to start and top end was lost.

The engine still feels strong with good throttle response.

Had to return the product and get NGK g-powers which worked awesomely in my car

Well after 40,000 Miles, one of the plugs fouled out, (not sure which one or if it was more than one plug that failed), the car just started to sputter as I hit the gas on the Interstate the other day