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Hi guys Just some thoughts on spark plugs for S4

I realised it was time for scheduled plug change and that they would be pretty nasty after 40k miles.
I did some reearch on various forums and found that stock plug is NGK's PFR6Q which is a doubleplatinum plug (both electrodes are platinum) and that this is regarded as a good plug. They seem expensive at about £11 per plug, but quality.
Right, I found that Champion's new EON 1 fits and tried them. What i found was interesting: although it is only a copper-electrode plug (pretty soft and short-lasting by today's standards) I found that there was a considerable improvement in performance. I was obviously unable to ascertain whether this is because the EON 1 is a better-performing plug, or the old NGKs were simply knackered after all those miles.

SO I did more research and found rave reviews about these ultra-hard, ultra-tiny Iridium electrode Denso plug. (IK20 is the model number) I get 6 for $45 from America on ebay and whack them in the car. These are regarded as the very highest-performance plugs that money can buy and I have found them to be inspeparable from the standard-tipped copper Champions. No impressive gains like when i replaced the worn old NGK. No better or worse than the EON1s

So I postulate that the important thing with spark plugs is to keep them new - change them regularly NOT how much they cost/how hard the electrode material is PROVIDED that you are prepared to pay £25 to have them put in reguarly NOT only every 40k miles.


Hope some of you find these interesting and useful, if only for compatible plug models.

PS Saw an RS4 today at Lindale Audi with an rs246.com sticker in the window - anyone here?
ATB Richard Utting

The NGK's are available for about £6 from a motor factors. and yes you are correct in saying that they are the same as the standard Audi ones.

I had problems with IK20's when chipped. The gap is higher than stock and the spark was being 'blown out' under high
boost. I re-gapped them to 0.032 instead of 0.040 and they seem to be OK. I have some IK22's ready to go in but
haven't been arsed to fit them. It's cold now as well...

What are the details to get the Iridium plugs? Make/type?

Thanks,

Denso IK20 (stock heat Range)
Denso IK22 (Colder, recommended for chipped cars)

www.spark-plugs.co.uk

IK22s have smaller gap, by the way. It's a normal 0.8mm gap, unlike the IK20's 1.1mm (.03 and.04ish respectively)

"K22s have smaller gap, by the way. It's a normal 0.8mm gap, unlike the IK20's 1.1mm (.03 and.04ish respectively)"

Well, I was told this. The IK22's I received have 0.04 written all over the packet. I haven't got a gauge and checked
the gap yet though.