DENSO makes a spark plug for every personality – from 100,000 miles to 150+ mph!

Welcome back! Let’s continue our look at the world of DENSO’s spark plug innovation. Today: the OE-Type Series.


U-Groove spark plugs – even DENSO’s “standard” spark plug is something special. The innovative U-Groove design helped make DENSO spark plugs famous with its unique, channeled ground electrode that is designed to generate a larger spark nucleus at the point of ignition. And, greater spark energy than ordinary plugs means improved flame travel, producing more complete, consistent, and efficient combustion.

Technically speaking, this design creates a larger spark and hotter flash front when the plug fires, virtually eliminating fouling and erratic starts caused by poor fuel mixtures while delivering better fuel economy and improved throttle response.

comparison of U-Groove and spread of flame nucleus


  • 100% pre-fired to ensure reliable operation
  • Patented U-Groove design
  • Copper core center electrode
  • Nickel ground electrode

Double Platinum spark plugs – DENSO was one of the first to pioneer Platinum spark plugs, which provide extended spark plug life in excess of 60,000 miles. This design incorporates platinum on both the center and ground electrodes, which translates into a significant improvement in spark plug life.

Conventional platinum plugs use platinum for only the center electrode, while the DENSO Double Platinum plug features platinum on both the center and ground electrodes. This precious metal fights corrosion and erosion, ensuring superior spark performance and maximum spark plug life.

Platinum durability comparison chart


  • Platinum center electrode
  • Platinum ground electrode
  • 360 degree laser welding

Iridium Long Life spark plugs – these were the world’s first automotive spark plug to use Iridium, providing sustained spark performance over 100,000 miles – that’s three times longer than conventional spark plugs.

DENSO’s patented iridium alloy is more durable than even platinum – and that produces a dramatic improvement in ignitability and spark plug life.

DENSO’s ultimate long-life spark plug comes factory installed on the latest high performance and luxury vehicles by automakers such as Toyota, Lexus, GM, Cadillac, Honda, Acura, and Mitsubishi.

In technical terms: Using our patented Iridium alloy and patented 360° laser welding process, DENSO was able to shrink the center electrode to 0.7mm, dramatically improving ignitability and achieving the ultimate longevity – longer than any other OE plug available.

Iridium LL Charts


  • 0.7mm Iridium center electrode
  • Platinum ground electrode
  • 360 degree laser welding

So, which of these spark plugs is right for you? Next week, we’ll look at the reasons you need DENSO spark plugs, no matter what you drive.

Find out more about DENSO parts for your car