Best and worst spark plugs and why.

IMHO Champion coppers are the best. I've got it in 84Isuzu Pup, could easily get pass through 50K miles or more. Just require re-gap every 20K. It is also the original plug on my old B&S push lawn mower. The plug outlasted the 4 wheels of my push mower.
 
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Originally Posted by Reddy45
E3 are gimmicky right?

NGK tried a plug with a similar design in the late-80's. Instead of the asymmetric angled cutout, it had three round holes in the platform. They were proud enough of them to give them a snazzy marketing name I don't recall at the moment, and even got BMW to spec them as OE.

That was short lived, as they discovered that it interfered with the operation of the knock-control system. A bulletin was issued to replace them with a simpler dual-electrode design.
 
OE for me.

Chinese no name would probably be the worst. That or anything aftermarket that claims to actually give some sort of gain.
 
OEM is always a safe bet but by no means mandatory.

I have had good luck with Autolite Platinums/double Platinums and the XP Iridiums, Denso TT, NGK etc. The only plug that ever gave me issues were Bosch. This was on several different vehicles. Another note is the stock plug on my 2008 CTS 3.6DI were Bosch finewires...they lasted 40k until misfiring. Same on my Dad's similar CTS - under 50k miles needed plugs. I went with another plug and they all went well over 50k. I had tried Bosch Fusion +4 on my Sierra and power was flat and my Tech 2 showed misc small misfires on the misfire counter. Swapped them out in the 2nd week and issues gone. I tried Bosch Platinums back in the 90's on my 3.8 turbo Buick GN and they were terrible so went back to AC Delco basic copper plugs on that car. I think now I have Autolite Coppers in there with no issues. Also have NGK copper in my Jeep CJ7 with no issues. So I don't use Bosch at all anymore, not worth the risk to me. Other plugs to NEVER use is the E3 and Pulstar gimmick plugs.
 
I usually use ngk. OEM on my vehicles is ac Delco and I refuse to spend another dime on their products since most are garbage.
 
I used Bosch spark plug on japanese engines in the 90's it's a hit or miss even though right # and gap.Stayed away from it.Now used whatever OE plug in there
mostly NGK.
 
Originally Posted by caprice_2nv
I usually use ngk. OEM on my vehicles is ac Delco and I refuse to spend another dime on their products since most are garbage.

Hope you're sitting down-the 8 AC Delco iridium plugs I just bought for the 6.0 Express in my sig look just like NGK (smooth insulator, no ribs). Fraction of the NGK price too! I'm with you on other AC Delco aftermarket parts, though, they're slapping their name on (I.e. licensing) everything, good or bad.
 
I ran Bosch +2's in a Chrysler LHS with the incredible 3.5L HO engine. No issues. I think my new VW comes with Bosch plugs too.
 
The OE version of the Genuine part recommended by the automaker for the vehicle in question. From what I've seen those who switch brands tend to have more issues.
 
Yet my BMW R150RS absolutely LOVES the 4417 Bosch +4 plugs over the OE garbage 2 electrode NGK. Better starts, better idle, no pinging. Never wore one out, I did replace after 24K miles because the gasket was leaking after being removed and put back in 3 times. It all depends on a lot of things.

Rod
 
Originally Posted by bullwinkle
Originally Posted by caprice_2nv
I usually use ngk. OEM on my vehicles is ac Delco and I refuse to spend another dime on their products since most are garbage.

Hope you're sitting down-the 8 AC Delco iridium plugs I just bought for the 6.0 Express in my sig look just like NGK (smooth insulator, no ribs). Fraction of the NGK price too! I'm with you on other AC Delco aftermarket parts, though, they're slapping their name on (I.e. licensing) everything, good or bad.


I was told ngk makes the Delco plugs. I've never had an issue with Delco plugs and used them because I knew the part number of the top of my head r45ts, but I refuse to give them any of my money now. Most entry level to mid level parts you're probably better off buying white box than ac Delco.

My Oldsmobile has had Bosch Platinum, ac Delco and NGK. They all worked fine actually.

The truck has had Denso and now NGK.
 
For the 1MZ-FE, the best spark plugs are the Bosch Platinum-Ir Fusion #4501 or 4503. Toyota used a twin-prong platinum Denso or NGK, but platinum is only good for 60k, and the job is almost impossible on those cars. The Bosch is a 4-prong iridium that will last at least 100k

Bosch is great when they are the OE supplier

Otherwise, Denso or NGK.

In particular, I like to upgrade to iridium where the job is difficult. The NGK Laser Iridium or Denso Iridium TT are both good choices (can't use the in the 1MZ because of the 2-prong requirement, but most cars have regular 1-prong plugs, so you can replace them with no problem)

I never use Autolite or Champion.

If only Bosch, Denso, or NGK would make an iridium replacement for those stupid 2-piece things on the Ford 3V
smirk2.gif
 
Originally Posted by slacktide_bitog
For the 1MZ-FE, the best spark plugs are the Bosch Platinum-Ir Fusion #4501 or 4503. Toyota used a twin-prong platinum Denso or NGK, but platinum is only good for 60k, and the job is almost impossible on those cars. The Bosch is a 4-prong iridium that will last at least 100k

Which 1MZ-FE? The ones with waste spark or the ones with six coils?
 
Originally Posted by caprice_2nv
Originally Posted by bullwinkle
Originally Posted by caprice_2nv
I usually use ngk. OEM on my vehicles is ac Delco and I refuse to spend another dime on their products since most are garbage.

Hope you're sitting down-the 8 AC Delco iridium plugs I just bought for the 6.0 Express in my sig look just like NGK (smooth insulator, no ribs). Fraction of the NGK price too! I'm with you on other AC Delco aftermarket parts, though, they're slapping their name on (I.e. licensing) everything, good or bad.


I was told ngk makes the Delco plugs. I've never had an issue with Delco plugs and used them because I knew the part number of the top of my head r45ts, but I refuse to give them any of my money now. Most entry level to mid level parts you're probably better off buying white box than ac Delco.

My Oldsmobile has had Bosch Platinum, ac Delco and NGK. They all worked fine actually.

The truck has had Denso and now NGK.


I pulled one of my plugs from my 03 Suburban 5.3.
It had a Delco and a NGK number.
 
Originally Posted by Reddy45
E3 are gimmicky right?


Yes, and I'd probably never buy one again but they work..at least on a chain saw. I'm not a gimmick guy (who else remembers Splitfire!!!), and I cant see the hokey looking E3 electrode being much of an advantage, but the plug on my old chainsaw was at its end, we had a tree down and the closest garden store only had, you guessed it, E3. That was probably 6 years ago and it is running fine, plug cleans up nicely and I will admit that it sure seems to be functional...
 
Originally Posted by kschachn
Originally Posted by slacktide_bitog
For the 1MZ-FE, the best spark plugs are the Bosch Platinum-Ir Fusion #4501 or 4503. Toyota used a twin-prong platinum Denso or NGK, but platinum is only good for 60k, and the job is almost impossible on those cars. The Bosch is a 4-prong iridium that will last at least 100k

Which 1MZ-FE? The ones with waste spark or the ones with six coils?


The waste spark version
 
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