The freebie Denso plugs arrived this week and I was wondering just how much better they are than the NGK platinum plugs that are fitted at the moment ? The NGK are new as the 60 k service was only a short while ago and it will take about 3 yrs !!!! for the next plug change. If Denso Iridium are much better then I will use them but are they ??

Opinions please.

Thanks

Brian

 

Stick with the NGK I say.

 

You don't say what car you,ve got or any mods that may benefit from the use of a colder plug etc. What grade are they?
I used Denso iridiums in the past in a modified Classic and they were fine. I'm now using Blitz (NGK) iridiums (heat grade 7) in my STi which has around 320 - 330 bhp and again, they're fine.
JohnD

 

Ooops , sorry about that, details do help.

Car is a Forester T/tb automatic (JDM) 1998. Engine mods are limited to a Sti air filter, Samco turbo hoses, HKS decat downpipe and Trust backbox. JDM output is 240 bhp, mods give about 260 ish.
Plugs are Denso IK20*4 5304*4 as sent by Denso for the Forester.

Cheers

Brian

 

NGK's I'd say.

The Denso plugs have had some bad press on here for 'tips' falling/breaking off!!!

Obviously resulting in piston/bore/valve damage etc....

 

Just fitted the Denso's today. I have had them a while but just got round to fitting them. They seem beter than the ones i took out but they have been in for ages now so i guess an improvement should be expected. Ill let you know in a few weeks if there is any problem.

 

I remember that, but I think the car(s) involved had some fairly serious power outputs?
JohnD