iridium & platinum????

[emac]

Mate I think you are missing the point, oh and I don't know what sort of car your wife drives but my Mazda 6 requires the plugs to be changed at 100 k intervals and yep their still running and look ok, however I'm assuming the manafacturer knows what he's talking about, as if one fails and starts through ini codes where do you start if you don't maintain the service schedule,

Now with the xj the champion plugs last for years assuming everything else is ok.

From my limited (19 years) experience with jeeps, the best thing you can do is improve the exhaust system and get rid of the mechanical fan and do electric fans.

Unless you are building a strokerr or hot roding the existing motor, balance reciprocating parts doing head work etc, everything else is just chucking money in a hole.

Oh and if you really want to wake it up re gearing works.

Specialty spark plugs...... Total waste of time and money.

However as I said earlier a hotter coil works for me.
But hey it's your time and money so try it out

[ATOMICPUNK]

Originally Posted by emac

Mate I think you are missing the point, oh and I don't know what sort of car your wife drives but my Mazda 6 requires the plugs to be changed at 100 k intervals and yep their still running and look ok, however I'm assuming the manafacturer knows what he's talking about, as if one fails and starts through ini codes where do you start if you don't maintain the service schedule,

Now with the xj the champion plugs last for years assuming everything else is ok.

From my limited (19 years) experience with jeeps, the best thing you can do is improve the exhaust system and get rid of the mechanical fan and do electric fans.

Unless you are building a strokerr or hot roding the existing motor, balance reciprocating parts doing head work etc, everything else is just chucking money in a hole.

Oh and if you really want to wake it up re gearing works.

Specialty spark plugs...... Total waste of time and money.

However as I said earlier a hotter coil works for me.
But hey it's your time and money so try it out

on the contrary....
Service schedule (manufacturer) for wife's car plugs is 160K.
Iridium plugs....not a specialty feel good item.....standard issue on many vehicles....waste of money, not a chance..new standard plugs every 20-40K v 160K...you do the figures.

as for the standard fans, I beg to differ
Im running factory fans, tho the mech fan I have modded slightly to pull more air and have installed foam/rubber sealing between the shroud and radiator so as air is pulled only in that section of the mech fan...the rest of the cooling system is factory, although new radiator, pump, clutch and PGXL coolant....runs like a dream, temp gauge has so far never been over half way, AC on, hot ambient temp or not...better than I'd hoped after reading many articles on here.

anyway, i know what you think of anything other than standard for your XJ,
maybe someone who has ventured onto the wild side and has tried or is using iridiums or platinum plugs to give their opinion

[emac]

go buy the plugs try them out and report back, don't dream about it do it

And have a great day

[rustynuts]

Ok fella's.
Here is my opinion and only just my opinion on Platinum/iridium plugs in an XJ.
All my spark plugs in all the cars I've ever owned have all been "standard" plugs. They have all lasted me over 100 000K's.
On my last ride, an old Rodeo 4cyl Efi I changed the plugs after driving it for more than 200 000K's. They were the plugs that were in it when I bought it and who knows how long they had been there for. There was nothing wrong with them when I replaced them. They were standard plugs.
Platinum/iridium plugs are a fairly new idea. From what I believe they were developed for modern performance engines. As engine manufacturers have pushed for better emissions and fuel economy, engines on ULP can be running on the verge of detonation or "pinging". These engines can sense the knock and the computer then compensates around this. See a lean mix and an advanced spark gives these engines economy and good emissions.
A knock is not good for spark plugs. If exposed to knocking the plug gets eaten away. It can actually blow bits off it. That is why these exotic plugs were developed.
IMHO a good running XJ does not need an exotic plug. Oh, and don't believe those plugs are really made out of what they are called.

[emac]

Yep

[ATOMICPUNK]

over 200K on standard plugs...wow, and iridium service life is more than double that of standard plugs.
actually, finewire plugs have been around a long time, just the centre electrode materials (platinum and the iridium)have varied. made for longevity and no need to regap (almost no erosion) and the fine wire electrode for lower ignition voltage requirement and contribute to improving the spread of the flame front in the combustion chamber.

thanks for your opinion....
have you used iridium or platinum in the XJ?

[emac]

And that's why I say again try them out and report back.

No one is using them, and there's a reason, but hey we might all be wrong, so go on shell out the money do it and then let us all know

How hard is that