My 1991 MX6, 2.2l, needs new plugs. I have 115,000 miles on a set of Bosch Platinum +4's and they're finally starting to misfire. I bought the +4's because they had the highest platinum content at the time (everyone knows that they don't create 4 sparks, but the open design might help flame propagation and offers 4 grounds to wear down rather than 1). I've been very happy with these plugs and their service life.
2 of my plugs are seized and I may need a heli-coil repair after removing them. So I'd like to put another very long life plug in to avoid dealing with them again. The options are:
-NGK Iridium (very popular and $)
-NGK Laser Platinum (apparently the best NGK plug for my application, but $$$)
-Autolite Double Platinum (allegedly long lasting and quite affordable)
-Bosch Platinum or Fusion +4 (I've had great experience with these and they're medium priced)
Iridium seems to be the flavor of the week in spark plugs and everyone loves the NGK Iridium IX. But interestingly they are rated as having a shorter service life than the "Laser" Platinum. I'm guessing this is because the "Laser" series of NGK has Platinum on the ground (side) electrode, as well as Platinum (or Iridium) on the ground electrode. NGK says these expensive Iridiums are good for 40k to 50k miles, while the Laser Platinums are ok for 80--100k: http://www.ngksparkplugs.com/pdf/DYK_LaserIridium_vs_Iridium IX.pdf
The double precious metal plugs are designed for Distributorless Ignitions, which in some designs fire in reverse on half of the cylinders. So the spark jumps from the side (normally the ground) electrode to the center electrode, rather than the conventional center to side. These systems NEED double platinum, or a normal side electrode would wear prematurely. You can read about it here: http://am.delphi.com/news-spotlight/tech-tips/ignition-electronic/
Which brings me to a very inexpensive set of Autolite Double Platinum plugs, similar to NGK's "Laser" series (with double precious metals on both electrodes). Autolite claims they're good for 100k miles, which easily should outlast my car.
Before everyone chimes in with "I use brand X, and it's just super" I really don't care about branding or what type of plug worked well for the last 30 years, or which one people had trouble with in a car 10 years ago. These are very different from conventional spark plugs and likely aren't made by Autolite anyway. I'm really not a fan of Honeywell/Allied Signal products (certainly not their orange oil filters, or their jet engines, all are [censored] IMO) but these plugs might be a good purchase.
Anyone have any experience with Autolite Double Platinums?
2 of my plugs are seized and I may need a heli-coil repair after removing them. So I'd like to put another very long life plug in to avoid dealing with them again. The options are:
-NGK Iridium (very popular and $)
-NGK Laser Platinum (apparently the best NGK plug for my application, but $$$)
-Autolite Double Platinum (allegedly long lasting and quite affordable)
-Bosch Platinum or Fusion +4 (I've had great experience with these and they're medium priced)
Iridium seems to be the flavor of the week in spark plugs and everyone loves the NGK Iridium IX. But interestingly they are rated as having a shorter service life than the "Laser" Platinum. I'm guessing this is because the "Laser" series of NGK has Platinum on the ground (side) electrode, as well as Platinum (or Iridium) on the ground electrode. NGK says these expensive Iridiums are good for 40k to 50k miles, while the Laser Platinums are ok for 80--100k: http://www.ngksparkplugs.com/pdf/DYK_LaserIridium_vs_Iridium IX.pdf
The double precious metal plugs are designed for Distributorless Ignitions, which in some designs fire in reverse on half of the cylinders. So the spark jumps from the side (normally the ground) electrode to the center electrode, rather than the conventional center to side. These systems NEED double platinum, or a normal side electrode would wear prematurely. You can read about it here: http://am.delphi.com/news-spotlight/tech-tips/ignition-electronic/
Which brings me to a very inexpensive set of Autolite Double Platinum plugs, similar to NGK's "Laser" series (with double precious metals on both electrodes). Autolite claims they're good for 100k miles, which easily should outlast my car.
Before everyone chimes in with "I use brand X, and it's just super" I really don't care about branding or what type of plug worked well for the last 30 years, or which one people had trouble with in a car 10 years ago. These are very different from conventional spark plugs and likely aren't made by Autolite anyway. I'm really not a fan of Honeywell/Allied Signal products (certainly not their orange oil filters, or their jet engines, all are [censored] IMO) but these plugs might be a good purchase.
Anyone have any experience with Autolite Double Platinums?