NGK Iridium Spark Plugs - Heat Range 6, 7, 8 or 9 - Nissan 300ZX Z32

For years we searched for the "right" plug for high HP, high boost applications on our own Zs. After testing numerous spark plugs we found the absolute best plug money can buy. Trying to find an adequate plug colder than the PFR6B-11B proved to be tough, but these plugs deliver the best spark around.

Comes in a set of 6.

Heat Ranges Available:

• The "6" heat range we recommend only for NON-TURBO engines.
• The "7" heat range is an excellent all around plug. Work great for direct stock replacement applications and modified vehicles. Great for anything under 20 psi. Works great on non-turbos. Great in cold weather applications.
• The "8" heat range is also a great all around performer. Allows one to run higher boost levels than 20+ safely, yet is hot enough for daily street use. Perfect plug for California style climates all year round. Works good with low nitrous shots too. We use this heat range in most of our tuned Z32s.
• The "9" heat range is the cold daddy of plugs. Recommended for extreme boost pressures (28+psi). It has weak cold performance due to fouling easily in cold conditions. Recommended to be used at the race track only (road circuit drag). The only plug to use for high boost and nitrous applications. Not recommended for daily driving.