Engine IRIDIUM vs Platinum Spark Plugs?

IRIDIUM vs Platinum Spark Plugs?

for a 2000 Corolla that i have, i have the stock spark plugs that came with it. I want a simple performance boost, which is better?

you should only use Iridium plugs.

iridiums are MUCH better for our vehicles-the same makers, NGK and Denso are the oem plugs that originally come with the car-platinums are not for our cars...

Stick with the OEM !!! So your saying that 1.8 is not THE most powerful car of all time ??? CW

how much of a performance boost will i get switching from stock toyota plugs wit 36k on the car

dont expect much-shifting will feel a little smoother-you'll feel slighty less hesistation when going uphill and a little more responsiveness-but it aint much-i did NGK iridiums, new NGK wires, and a new distributor cap and rotor all at once-it felt a little better-not much-i guess it depends on how warn out the older plugs are..

platnium is the lazy mans spark plug since it dosen't require changing for 100k+ miles.. Iridium is a far more conductive metal..

you won't get much boost in performance by just changing the plugs.

go iridium

i just use NGK's in both of my cars.....

well, i would use what came stock..... if you need a hotter/colder plug take your plug in to an automotive parts store and tell them you want the same, but hotter/colder...

VVTi engines (2000+) require iridium plugs.

Iridium should last just as long or longer than platinum, as it is a much harder metal. Additionally, it offers higher electrical AND thermal conductivity than platinum:

Iridium
Hardness 6.25 mohs
Thermal conductivity 147 J/m-sec-deg
Electrical conductivity 188.679 1/mohm-cm
Platinum
Hardness 4.3 mohs
Thermal conductivity 71.6 J/m-sec-deg
Electrical conductivity 94.34 1/mohm-cm

However-- if you intend to use the same spark plugs for 100,000 miles, use a good anti-sieze compound and remove, inspect, and (unless they require replacement) reinstall them every 40K-50K miles as it is possible they will sieze in their threads over time.

Go for copper. Doesn't last as long, but is cheaper and conducts better than iridium.

im currently running bosch platinum+2's in my 2001 prizm, i swapped out the denso iridiums.. the engine runs smoother with the platinums and it even seems to be a little more powerful, but that could just be from putting in brand new plugs compared to plugs with 70k miles on them..

i cant escape the fact that the engine runs much smoother and gets better mileage on the platinums though..

iridiums are certainly not a requirement for any naturally aspirated vehicle on the planet.

its true that iridium is harder than platinum, however, at its limits it becomes brittle, much like titanium.. it is not ideally suited for high stress environments such as boosted applications... in any NA vehicle its fine..

also, platinum is less expensive and less rare than iridium, so more platinum can go into a plug rather than most iridium plugs in which only the tips are iridium.. platinum also produces a larger and hotter spark, which is very beneficial in NA tuning, especially when high compression is a factor ( not an issue for our cars ).. platinum, like iridium, does not hold up well under boost.. copper is definitely the best for that situation..

but wait.. ive gone off topic

hmm very interesting stuff. Maybe i should get iridium, or just get a 4 prong platinum plug