Best Spark Plugs Ever Used
 

Iridium High Performance Plugs that Really Make a Difference

http://www.densoproducts.com/product...ctCategoryID=1

Best Spark Plugs Ever Used
 

Iridium High Performance Plugs that Really Make a Difference

http://www.densoproducts.com/product...ctCategoryID=1

Re: Best Spark Plugs Ever Used
 

They come pre gapped. ?

Re: Best Spark Plugs Ever Used
 

They come pre gapped. ?

Re: Best Spark Plugs Ever Used
 

USE THE NGK ONES

Re: Best Spark Plugs Ever Used
 

USE THE NGK ONES

Re: Best Spark Plugs Ever Used
 

I personally don't like precious metal fine wire spark plugs, especially the iridium plugs. Sure, they last 3x as long, but cost 4x the price. For someone like me who changes their own plugs, this doesn't make financial sense. Fine wire plugs electrodes, kind of like sharp edges in your combustion chamber, run hot and can cause detonation. This is one of the reasons you'll never see a precious metal plug on a race car. The double platinum and iridium plugs have a platinum or iridium wafer bonded to the side electrode. Under detonation, it is possible to dislodge this wafer and now you have a very hard piece of metal floating around in your cylinder.

I go through a lot of spark plugs, we've got 44 cylinders in our driveway. 2 v8 trucks, 2 v8 cars, a v8 boat, a lawn mower, and 3 1 cyl motorcycles. Spark plug quality control is very good, and I see little appreciable difference between brands. I've had one bad plug, an NGK, but I believe it was dropped at some point after manufacturing. I believe NGK and AC Delco make the best plugs, but wouldn't go out of my way to buy them. If Champion is available or on sale, that is what I would buy, and did. Autolites are at the bottom of the list, but I would buy them if the price was right.

Re: Best Spark Plugs Ever Used
 

I personally don't like precious metal fine wire spark plugs, especially the iridium plugs. Sure, they last 3x as long, but cost 4x the price. For someone like me who changes their own plugs, this doesn't make financial sense. Fine wire plugs electrodes, kind of like sharp edges in your combustion chamber, run hot and can cause detonation. This is one of the reasons you'll never see a precious metal plug on a race car. The double platinum and iridium plugs have a platinum or iridium wafer bonded to the side electrode. Under detonation, it is possible to dislodge this wafer and now you have a very hard piece of metal floating around in your cylinder.

I go through a lot of spark plugs, we've got 44 cylinders in our driveway. 2 v8 trucks, 2 v8 cars, a v8 boat, a lawn mower, and 3 1 cyl motorcycles. Spark plug quality control is very good, and I see little appreciable difference between brands. I've had one bad plug, an NGK, but I believe it was dropped at some point after manufacturing. I believe NGK and AC Delco make the best plugs, but wouldn't go out of my way to buy them. If Champion is available or on sale, that is what I would buy, and did. Autolites are at the bottom of the list, but I would buy them if the price was right.

Re: Best Spark Plugs Ever Used
 

been running these in my race car for yrs never had a problem best plug i ever used for times. The hotter the plug the wetter you run the hole. When you have $20k in the motor you don't skimp on cheap plugs. Nascar boys run them in AC Delco brand same i use, Some of the nascar boys run Bosh Platium, not i the racing fuel eats the platium coating off lol. I run AC Delco Iridiums in my Vette too they make a hugh difference in the running of it as well. WORST Plug i have ever used is NGK i never use them they are 100000% junk. Theirs 13 cars and 10 vessels in the yard so plugs aren't lack here either.

No they aren't pre gapped to your needs but easy to gap.

Re: Best Spark Plugs Ever Used
 

been running these in my race car for yrs never had a problem best plug i ever used for times. The hotter the plug the wetter you run the hole. When you have $20k in the motor you don't skimp on cheap plugs. Nascar boys run them in AC Delco brand same i use, Some of the nascar boys run Bosh Platium, not i the racing fuel eats the platium coating off lol. I run AC Delco Iridiums in my Vette too they make a hugh difference in the running of it as well. WORST Plug i have ever used is NGK i never use them they are 100000% junk. Theirs 13 cars and 10 vessels in the yard so plugs aren't lack here either.

No they aren't pre gapped to your needs but easy to gap.