Best Automotive Replacement Spark Plugs in 2020

Permatex 22058 Dielectric Tune-Up Grease, 3 oz. Tube Review:

When used correctly, this product will prevent water and other debris from reaching the terminal end of your spark plug. The product should be applied around the insulator portion of the plug and not reach deep inside the boot where the terminal end is. A dielectric is an electrical insulator, it does not promote an electrical connection but actually serves to prevent one. The purpose of the grease is to not allow water and other materials from seeping up toward the terminal end. I apply the grease around the insulator of the plug, then hand tighten the plug into the head. Tighten with a wrench as per your torque requirements (or just a little past snugged up) and press the boot onto the plug. The grease should form a barrier around the plug insulator, preventing stuff from working its was up the plug and from ultimately fouling the terminal end.

Permatex 81150 Dielectric Tune-Up Grease, 0.33 oz. Tube Review:

The world has not come together on all the exact application of the Dielectric greasy. Some people use it on almost everything and some get behind the "it doesn't conduct electricity". Of course it doesn't conduct electricity, it just help protect the components from corrosion -water-humidity-salt-dirt... But still is a debate where to use it. I have seen people on the internet using it on almost everything.
They show tests where you can see that it takes a extremely small amount of conductivity from the connection but is almost nothing if the connection is conducting a decent amount of energy.
I'm still not sure if I should get all the connections on my dirt bike and just make sure they are protected or if I gonna create a bigger problem. I guess I'll start by doing a few and if nothing bad happens ...i'll just continue.
These may not help that many people but I put out there what I have found.
BTW the tube is bigger than I thought what it's nice! :)

UPDATE: I have used in every possible connection I have found on my Yamaha TW200 and so far I haven't have any problem. The only thing I haven't tried yet are fuse... everything else it's been working fine for months. :)

Champion RC12YC Spark Plug, Pack of 1 Review:

This is a common plug for many small engines- but make SURE you use the correct plug for your particular engine. I'm not sure what else one can say about a spark plug as far as reviewing it- it sparks when asked to. It arrived undamaged. My suggestion, having been a gearhead for decades, is to stick with name brand plugs. There are some really odd plugs on the market but in a small engine, exotic plugs usually don't have any benefit. This is also true with many cars, but results vary wildly in larger engines. Keep it simple- the good old Champion 12YC has been around forever and is the plug that many engines come with from the factory... at least mine did.

NGK (7131) BPR6ES SOLID Standard Spark Plug, Pack of 1 Review:

My Sears Craftsman lawn mower has a Honda motor and it takes this spark plug. So every year I begin the mowing season with one of these new spark plugs, a new blade, fresh oil, and a clean filter. Everything together costs only about $20 and that small investment means a mower that will last at least a decade.
This mower has a few good years left in it, but it will likely be my last gasoline mower. When this one goes, I'll likely pick up a battery electric Ego mower from HD. No more spark plugs for me (and I can dump the ear plugs too).

NGK 7090 BKR5EGP G-Power Spark Plug, Pack of 4 Review:

NGK has always worked phenomenal for me. I've used from their standard plugs to their iridium plugs. They all perform well, in fact their most standard plug works just fine for average driving and regular change intervals. Ive pulled standard NGK's from old cars and scraped off fouling deposits to show a still functional gap with minimal corrosion. Platinum just seems to have these deposits blow off easier from combustion. (just a theory).

Always a fan of just the simple platinum spark plugs. These fit the bill perfectly. IMHO, I rather buy more cheaper, competent plugs and replace them at shorter intervals than buy expensive "higher mileage" plugs just to keep them in longer. This way I have fresh plugs that spark just as well for a complete burn. I am always wary of having things like iridium plugs in for the last 1/3 of its "life." I always feel they start to become suboptimal and replacing them any sooner is just money down the drain.

Besides, changing spark plugs are not difficult.

6 PCSNEW -- DENSO #4503 PLATINUM T T Spark Plugs -- PK16TT Review:

These fit my 2007 RAM 1500 V6 3.7L engine just fine.
One thing to note, all the spark plugs came pregapped at exactly 0.035. After looking at my engine compartment decal, my engine calls for a gap of 0.040 (which is odd because online RAM says it should be 0.044). Now, 0.035 is probably fine to put in as they will expand slightly, but I gapped them to the spec from my engine compartment regardless (maybe I'm a bit over concerned). Be sure to check the gaps and adjust to what your engine compartment specifies. So far, I haven't had any issues with these plugs and they seem like good quality.

NGK 2667 BKR7EIX Iridium IX Spark Plug, Pack of 4 Review:

For some incorrect reason, Amazon's "Garage" feature will say "This product does not fit your vehicle" if you have a MKV VW GTI 2.0t. On the contrary, it does fit. Many online VW tuning shops sell these exact plugs for use in Audi A3 / VW GTI / Jetta GLI / etc.. So your good to go.

I installed these and the car runs smoother. Strong pull throughout all the RPM range. I had 59k on the stock BOSCH plugs. The stock plugs had seen better days and cause misfires under heavy acceleration. Replacing them with these NGK BKR7EIX solved my problems and the car feels new again.

Its a simple install on the 2.0 t motor and you can google search some good instructions with photo's online. I did it myself. Plugs are gapped appropriately from the factory for this application.

NGK (3951) TR55 V-Power Spark Plug, Pack of 1 Review:

I installed these in my 2004 Pontiac GTO today. Even though Amazon states they don't fit, they do. I did my research, plus know the GM LS1 platform and these are popular in Corvettes, Camaros, and GTOs, all which have the LS1 engine. Torque specs are 11 ft lbs for the GTO. Didn't have any problems installing the plugs. I used ACDelco wires which matched up perfectly with these. I also checked the gap on the plugs and they all were set to .050 which is within tolerance for the GM LS1. These plugs have a copper core, so you will need to change them 30,000 miles.

NGK 7090 G-Power Platinum Spark Plugs BKR5EGP - 6 PCSNEW Review:

Work well in a 2000 Mercedes CLK430. Good luck getting the back ones out next to the fender wells but it can be done. Take the windshield washer tank out on the drivers side. Easy to do and makes a huge difference. Oh and an open end 3/4 inch wrench can be used on the metal spark plug boots to pry them off if they are difficult.