(T) VXU22 spark-plug gap for a 1.2

hey again - I've just read an excellent thread on 1 million different options on spark-plugs and mpg and power and longevity and....

But I am slightly puzzled.

For a 1.2 Lounge MY12, what gap should be set for the Denso Iridium Tough VXU22 please?

0.8
1.0
other

Thanks

I was told some time ago that new plugs come with the correct gap and don’t need adjusting.

Thanks!....but that would be for 'standard' plugs for a 'standard' application.

I think as the 'upgrade' VXU22 is applicable for many different engines, it can't be gapped perfectly for all of them.

Yes it can. For all its applications, the gap it is supplied with is the one it should use. Most plugs don't show or advise gaps to discourage anyone messing with them and getting it wrong. Setting the gaps on these plugs with tiny electrodes can easily lead to damage of the electrode.

On any plug, never close the gap below its standard setting. It leads to a weaker spark, as the voltage to jump the smaller gap is less, so it jumps before it reaches max power.

NEVER attempt to gap an Iridium plug. Do not even attempt to check the gap unless you know exactly what you are doing.

If you've ever checked the gap on an iridium plug with a ball type tool, dropped one, or even knocked the tip, put the plug in the bin now.

The tip is both exceptionally hard and exceptionally brittle; if it breaks inside the engine, it'll likely do considerable damage.

VXU22's come withe the gap preset to 0.8mm, and that'll work just fine in the 1.2. Being slightly smaller than the 1.0mm gap of the standard plugs, it'll put less stress on the coil pack, too - which is a good thing.

Iridiums gapped to 0.8 work very well in the 1.2 FIRE and are a useful upgrade for this engine.

thanks both.... maybe today people are discouraged to do anything mechanical or indeed electrical (wiring a plug? far too dangerous ) but in my day you made sure the gap was correct, and different applications for the same plug had different gaps.

I also always check that the gap hasn't been altered by a bump in storage or transit pre-purchase.

Looks like I can put my feeler gauge back in the bottom drawer.

There’s a cardboard tube around the spark plugs usually. You’ll be able to see if it’s had a knock.

sure - and these ones (unfortunately) have a plastic tube.

But I would always check the gap anyway. Why wouldn't you? As pointed out, if the gap is wrong there is a chance for proper engine damage.

If you have enough tools and wherewithall to change the plugs, shirley you can check a gap - where does responsibility start? or end?

Because the plug manufacturer specifically recommends that you do not.

The central electrode is fragile and easily damaged if subjected to any pressure. Best case, it breaks off and you ruin the plug. Worst case, it cracks and breaks later inside the cylinder and you ruin the engine.

Modern cars have evolved. If you try maintaining one the same way you maintained your Morris Minor, things aren't likely to end well.

errr yes that's a recommendation and a ridiculous cop out. Why am I not allowed to take responsibility for my own actions? Why are you making judgements on my levels of expertise?

Shame you take that attitude. A moderator should be moderate.

By all means recommend and advise - I'm afraid your attitude of 'do as I say' isn't one that I think is appropriate.

But thanks for the advice anyway. I'll try not to rock your boat any further.

ps never had a Morris - my list would bore you I'm sure. Other than maybe the Strada 130TC Abarth.

If you come here asking for advice then choose not to take it, why did you bother asking in the first place ?

Crack on then!

If you don't know never to "gap" Iridium plugs, then should one be replacing them in the first place? But for those who might be uncertain, they come ready to install.