JohnD

iTrader: (5)

I changed the plugs in my 03 STi (then PPP) for 7 grade Blitz (NGK) back in '04 and have since done 15600 miles. Changed them today for a set of Denso IK22.
On inspection of the old plugs it was clear that they probably could have done with changing some while ago! I remember setting them to 0.7mm, now a 0.8 feeler falls through and there is a crater eroded on the underside of the ground electrode, so the effective gap is wider than that! Have to admit, I've had no problems at all during the time they were in, it's just that the wear rate took me by surprise somewhat as iridiums are supposed to be long-life?
JohnD

Bob Rawle

John I would not use the IK22's, prone to dissapearing tips, risky, certainly not robust especially in a remapped car. I use Denso plugs but they are the IK01-24.

PFR7B's wouldn't last me more than 5k miles, the IK01-24 will do a good 15k, I just change them at that.

bob

JohnD

iTrader: (5)

What kind of spec. are IK01-24? Looked them up on Spark Plugs UK and they're over £30 each!
Although my car is mapped and running just over 1.4bar most of my driving is "normal" so I need a plug that is safe when asked to perform but also tolerant when pootling around.
As I only cover around 6.5-7k a year, maybe PFR7B's changed yearly?
JohnD

hux309

Hks are denso plugs and are far cheaper but i will never put them in my engine as the electrode tips are known for breaking off and buggering up engines

In my old car i had a small piece chipped off, could have easily caused my piston rings to fail

Personally id rather stick with ngk's

harvey

iTrader: (48)

HKS Denso Iridium cost me a valve and a cylinder head on a high power STi 6 Wagon. For gentle work and nothing too heavilly modified, ie. less than 550 bhp, I use NGK PFR 7 B and after that it is NGK racing 8s which need changing at 5k intervals.

JohnD

iTrader: (5)

I was aware of the problems some people experienced with Denso iridiums but this was some while ago? I was assuming (naively?) that any such product failure had been corrected!
I've ordered a set of PFR7B's to replace the IK22's (might stick these in the wifes Primera - should be quite un-stressed in there!)
JohnD

Bob Rawle

John I am not suggesting that they are the right plug for your car, should have been clearer, whilst the "normal" Denso's (or HKS as they are just badged versions) are "not good" these have done me proud, so not all Denso plugs are "bad" iyswim. Expensive yes but they last over three times as long as the NGK's (in my car) so not really all in all.

PFR7B's will suit you, they ought to last between 7 and 10k.

cheers

bob