Spark plug creativity?

Topeka, Kansas, USA
1998 Chevy Tahoe
I'm about to replace the plugs, wires, cap, and rotor on my 1998 Chevrolet Tahoe. When I do searches in auto-parts store web sites with local stores, there is an incredible variety of plugs: platinum (stock, reportedly), double-platinum, iridium, "power nickel" (whatever that means). And when I go wider, Ruthenium?. Some friends recommended capacitor plugs -- but then some others told me that they tend to fail all at once, rather than petering out. Splitfires seemed to do well for me in a different vehicle a long time ago, and there are obviously much wilder ones. Anyone got experiences to share?

I'm running her with one of these remapping computers now, which I imagine will be able to learn what to do if spark becomes a bit off-stock. OBDII says misses on cylinder 4 only so far. Have wondered about replacing just one plug, but seems more prudent to replace all, this engine has 214,000 miles, has generally run very nicely, and not clear that replacement has ever been done. The motivation for this replacement -- lowest idle being rough -- began some weeks before the computer went on, have already tried some very trusted engine cleaners.
Check the #4 plug by installing in another cylinder and if it misses then it's faulty and if it doesn't then it may be a wire or coil if there are multiple coils Test the same method as per the plugs .

Regular plugs should be fine as it would take a dyno test to define any measurable power increase if any.

Would recommend replacing the condenser on the dissy if it has one.
You only get one spark from a twin tip or dual or quad electrode, the only argument for these is a larger surface area, which can help prolong plug life but it does nothing for performance.

How large a match do you need to start a forest fire? As long as you start a burn it will build and this is true also in an engine.

Iridium plugs last a very long time.

How can putting a resistor in a plug actually help? If anything it gives a shorter more intense spark as it limits the build up and tail off of the charge.

There also used to be a lot of claims made for plasma spark plugs but these didn't catch on and quickly died a death.

Overgapping used to be a thing to give a larger spark and better ignition at the cost of less tolerance of a weak spark charge.

The most important thing with plugs is to get the right temp rating for your car and replace or clean them when they get sooty. The coil is probably the only thing that can be improved, and even then there are practical limits.
Interestingly enough, the original OEM plugs on this truck (1998 Chevy Tahoe) were platinum -- but the GM recommend now for replacement is iridium. My favorite engine guy is a stickler for OEM standards (when I let him), which does keep me out of a lot of trouble; we were both surprised :) Running just lovely now. 215,000 miles, probably about time! Plugs, wires, cap, rotor.
Platinum and Iridium are long life plugs and some FWD V 6 motors have platinum in the rear bank as the inlet manifold has to be removed to replace the rear bank plugs and std plugs in the easily accessible front cylinders.
Over the years I have tried just about every plug out there except the newer E3's, back to back dyno runs, road use you name it. I even ran the Split Fires back in the day. Most had zero effect. Stock is usually the best. Iridium is supposed to last longer, so good choice.
I am using Ruthenium plugs but it's the special tipped design that comes side gapped with a shorter ground strap to have less material impeding the expansion of the flame kernel. It's a known way to squeeze a few more HP out of a forced induction engine. So far so good but it's only been about 6 months so I have no idea yet for longevity. In my engine the electrodes wear out faster than the ground strap, even double-iridiums last less than half of their advertised length before losing power which for me is about 20,000 miles.
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