I've run double platinum plugs in a G16 with no noticeable difference to performance or economy. I doubt a set would last 100,000km in that (G16) engine. Half that amount maybe...

I now run standard plugs and change them at every oil change. I don't ever have to worry about them 'cuase they are always fresh.

Just something I've heard is if your engine wasent designed to come out with them it'll do damage ie it'll get a hard carbon build up around the bottom of the plug and when you remove them it'll strip the thread on the spark plug hole and then you need either retap the head or get a new very costly and if it didn't come out with them don't put them in its what I've been told so it could or couldn't be true but just a heads up

Platinum plugs are mainly for engines like Subaru boxer engines which are costly due to disassembly.

What? Subaru's aren't that hard to get too.

Change plugs EVERY oil change? Wow I think that may be some overkill? I used to change platinum plug every race meet but that's in a 2 stroke race engine that can foul a plug in a heartbeat if not careful with throttle control, but in a car.....I had platinum plugs in my rx3 13b bridgy turbo and didn't change plugs until changed seals.
Just whack a set of plugs in and when they die.....if you still own the car... Replace them.

I use regular plugs so there is no guess-work as to if they are fouling or when they might be due for replacement.

According to the Sierra FSM, regular spark plugs (NGK BP5ES) should be replaced every 10,000km. I do a 6-7000km oil change interval - therefore I may as well spend 5 minutes changing the plugs at every service!

On my carby Sierras the plugs always look dirty when changed. On my EFI Vitara the plugs still look good so maybe in that instance a Platinum plug is more suitable.

Compared to other 4 cyl engines (like a J20A) they are.

How much difference do you notice by changing your 6-7k old plugs to newies?

Thats why you run ultimate fuel and flog the fuckin bejebus out of the engine for a few hundred K's before you change them. Thats the best way to decarbon a motor.

i ran a(no money spared) rebuilt, worked g13ba in the sierra for a while.. with splitfire plugs, put " iridium platinum" plugs in and they were fould up in
only 1 month of use...i ran that engine at 8000rpm on a daily basis and they still fould up... (not worth the money in my opiniun, but just my 2c worth)

i ran a(no money spared) rebuilt, worked g13ba in the sierra for a while.. with splitfire plugs, put " iridium platinum" plugs in and they were fould up in
only 1 month of use...i ran that engine at 8000rpm on a daily basis and they still fould up... (not worth the money in my opiniun, but just my 2c worth)

None - as to be expected.

The cheaper plugs are best, but iridium/platinum are mainly for longer service intervals, hard to get to places etc.

Mitsubishi's v6 used to have half and half!

My wife 05 rolla has them also from new. Too many covers and shit

Hmm.. So should get 3 standard and 3 platinum plugs for my Fagna?
I don't really wanna pull the intake off too often haha.

Spend money, notice no difference = money well spent