[Tazbear]

I've read numerous posts about which brand of spark plug to use for a Duratec and seems everyone is against using Bosch. Any one have any experience with or opinions about using Autolite Double Platinum?

 

[Sablewagon]

Autolites are okay, but what's wrong with Motorcraft?

 

[spridget]

Autolites and Motorcraft are exactly the same. Any other plug brand will be slighty different.

I just installed some Autolite DP's. So far they are working great!

(thanks to mykej27 for the plugs!)

 

[Tazbear]

Nothing wrong with Motorcraft. That's what I've been running for the past 100,000. Had tune up about 5,000 miles ago and fresh Motorcraft put in by the stealership and two of them are bad. Something about the center being cracked. Now I have Autolites to try out. Putting them in this weekend.

 

[HighTecRedneck]

I had posted these comments in the Bosch Platinum spark plugs thread a few days ago.

I had purchased Autolite DP's to install (to replace the stock Motorcraft platinum plugs) but Alberto (americanmotorsport.com) advised me not to install them or any other platinum plugs as I am getting ready to purchase a Mircotuner/chip from him.

He highly suggested Motorcraft Copper Core plugs one heat range colder then stock for my 98 Duratec. His reasoning follows.

Copper is a much better conductor of electricity, so it will in turn provide for a better spark. The reason the factory uses platinum, is simply for durability, as you have to change copper plugs much more often (30k vs 100k). People have, over time, begun to THINK platinum's are better...they are not.

One heat range colder than stock is better. The OEM tries to get the best emissions possible, so they try to run the cylinders hotter. If you run a heat range colder, you are in turn extracting more heat from the combustion chamber, and you can run a bit more aggressive of a tune, and guard against detonation.

They recommend Motorcraft, because they have seen the best results from them out of them all on the dyno and on durability testing.

I've had platinum plugs before for other vehicles but never noticed any noticable performance increase or decrease. However I'm going with Alberto's recommendation on this one as I trust his experience and all the recommendations he has received on this site.

I just pulled my motorcraft platinum plugs yesterday (original after 63K miles) and the electrode was very worn and melted. I sent Alberto a picture and he said that i would greatly benefit from replacing them with the cooper plugs that are one heat range colder. Hope that helps some with your decision.

 

[biteableniles]

I had autolite single electrode plugs (I don't remember why) in my Duratec for about 3 or 4 months before they crapped out on me. Experimented with Bosch dual electrodes, and all in all my engine is running a hell of a lot better (no misses, and...this is gay...a HELL of a lot cooler.)

Safest bet, though, would probably be to get OEM Motorcrafts.

 

[HighTecRedneck]

Just a follow up, i have the Motorcraft Copper Core plugs i previously mentoned instaleld now and they run GREAT. Looking forward to getting that program from americanmotorsport.com this week now.

 

[sixfofalcon]

Autolites and Motorcrafts aren't exactly the same, but you'd be hard-pressed to find any differences. Autolite is an aftermarket plug made to the OEM spec. Thus it has exactly the same design. Little things such as material sourcing or quality control traits might vary, since Autolite is made by Honeywell/Allied-Signal, and Motorcraft is made by Ford. However, I don't see one as being superior to the other... they are both excellent plugs.

 

[madness_spirit]

you could always try NGK iridium plugs iridium is more conductive than platinum, but because of its extreme hardness and high melting point, they can use finer tip electrodes. A finer center electrode takes less voltage to jump the plug gap, therefore generally platinum does preform better than copper due to the fact that platinum uses finer center electrodes, even though copper is a better conducter. However with iridium it is finer still therefore you require even less voltage than platinum and can get a better spark still. just really I cant emphasize enough that copper plugs use much much larger electrodes, so even if they conduct electricity better they require higher voltage to jump the gap. So technically you shouldnt get better spark with a copper plug. The reason ford uses the platinum plugs in the cars OE is so that the cars can produce better sparks on the relatively low voltage that our coils produce. Thereby making them more fuel efficient and getting ford more government grants.

BTW I have gone from copper to platinum plugs on many of my cars in the past and I have always found better performance with the platinum plugs. Of course that is because I always put in a performance ignition or supercoils. Although I still wouldnt use those bosch platinum +4 plugs since they are just much harder to gap correctly -- thats the reason a lot of people dont get as good of performance from them