If you are using nitrous or forced induction (boost) we recommend copper style spark plugs. Platinum and Irridium plugs have been known to break apart under boost/nitrous which can damage your engine. Copper style plugs are less likely to damage your engine, but the down side is they only last about 10-20k, so you will need to check and replace them more often. Please look at the Tech Notes to select which heat range of plug is best suited to your needs.
Includes 6 Copper Plugs.
Stock heat range is for light use of nitrous no more then 50hp shot.
1 heat range colder is for heavier use of nitrous or up 6psi of boost.
2 heat ranges colder is for lots of nitrous or boost of 6-12psi.
The plugs will last only 10K-20k miles.
1989-1995 SHO MTX
1993-1995 SHO ATX
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