Taff_o

Time has come to change my plugs on my STi V4, and advice on which are the best replacement plugs?

Taff_o

bttt

RichS

NGK PFR7B
or
DENSO PK22PR8

Not sure what the HKS numbers are..

Rich

Ian G

Rich
I was told NGK PFR6B, do you know the difference between the two - I think it's the heat rating - do you know which it better?

RichS

Ian,

PFR6B is listed for UK Impreza's.

PFR7B is has a cooler heat rating, and (as I understand it) is better suited to pre MY01 STi's.

I will double check this info. and report back tomorrow.

Rich

Danny Fisher

Be careful with the Denso plugs. A few people (myself included) have had the tip fall/burn off. I know that the HKS plugs are made by Denso, but I think to a higher standard.

Dan

Edited to add, HKS Plug code is S35i

[Edited by Danny Fisher - 4/17/2002 6:12:19 PM]

Taff_o

Thanks for that

RT

Denso's tip fall off?

Had one of mine IK22 blow at WOT, gear4. MY01 STI RA. Tip was still intact however. *phew*

Drove on 3cyl to my mech who replaced all. As soon as I got my hands on NGK's, I swapped back. Running NGK "Iriway" #8 now. Even colder plug, more suitable to our climate here. No fouling/misfire problems so far.

RichS

Spoke to the NGK technical department today.

According to their information, PFR6B is the listed plug, but they said that PFR7B would be fine as a performance replacement.
(The guy did have more information, but it was in Japanese and I didn't push him to get it translated.)

If you look at the Power Engineering website, they detail uprated NGK spark plugs next to a picture of PFR7B's.

Hope this helps....


Rich