john blaze

iTrader: (16)

how often are you suppose to change the plugs on evo 9? i changed my plugs last summer to one step colder plugs from denso, and recently im getting break outs on wot again. any info would be great thanks

sparky

iTrader: (1)

What exact plugs are you currently running?

Jeff_Jeske

iTrader: (66)

I have 18k miles of 50/50 leaded fuel and still haven't replaced the stockers. I think iridiums should be good for at least 50k miles.

But if you need new plugs EBAY seems to have the best prices for both Denso and NGK.

EvoVan

iTrader: (4)

Yeah, Iridium plugs are good for hella miles.

binky

iTrader: (11)

Honestly -

I change mine every 3,000 miles when I change my oil.

I run NGKBPR7ES. They are cheap and offer better detonation protection than iridium plugs.

The reason I change them that often is my car is not my DD and when the Evo is out and about I am usually putting it through its paces.



-Bink

pantspuppet

iTrader: (3)

There are two maintenance schedules for your car, regular and severe duty. Both schedules specify that plugs be changed every 60,000 miles.

Jeff_Jeske

iTrader: (66)

I can confirm that. Almost every mile on my car is a track day mile. Copper plugs need more attention but you wouldn't catch me running DSM plugs in an EVO. Plug technology has come a long way since then. No reason to run a Seadoo plug in an EVO.

pantspuppet

iTrader: (3)

EvoVan is right. You don't get much metal degradation with iridium so the gap won't open up very much over time. Unless they're fouled with carbon or oil, you shouldn't have a problem with your plugs. Have you taken them out to look at them?

pantspuppet

iTrader: (3)

Mitsubishi specifies NGK ILFR7H. Gap should be 0.5-0.6mm. If the gap is not right, get another plug. Don't adjust the gap on iridium plugs.

pantspuppet

iTrader: (3)

Torque spec. is 18±4 ft-lb.