Ford V-10 sparkplugs (SP 479 or AP 103)
I bought a old X with the 6.8 and wondered what's the best sparkplug to run. I seen Motorcraft SP 479 and Autolite AP 103. Any suggestions? I won't change them, I'll let the mechanic I use change t...
Forum Discussion
I've used both. I'm now running AutoLite iridium plugs. The platinum only last me ~60,000 and double still only about ~75,000 miles. This is because the tune I'm running which is pretty aggressive. The iridium let me make it all the way to 100,000 miles again. I don't feel they are necessary for a stock tune.
