Originally Posted by sdsguy (Post 6636804)

Hey guys,


I'm due for a spark plug change. I've read the spark plugs snap and it seems like a hell of an ordeal to do at home. I'm trying to decide if its worth it to take the car in for the dealership to do ($360 for plugs and fuel filter) or is it something easy enough to do at home. I've never done it before, the most I've done is clean my throttle body, install cold air intake. One of the things I can't find is at what point did Ford use different spark plugs to avoid the issue.

Any help would be appreciated.

Originally Posted by cdynaco (Post 6636808)

They changed the head design in 12.07. Bullitt's have the new design so don't worry about the plug nightmare. (Still be careful as with any plug change but you won't have the carbon issue on the old longer plug.)

The brown boot shows you have the new design:

Originally Posted by sdsguy (Post 6636810)

Thanks! Any tips for a first timer? Do I need a torque wrench or anything?

Originally Posted by cdynaco (Post 6636808)

They changed the head design in 12.07. Bullitt's have the new design so don't worry about the plug nightmare. (Still be careful as with any plug change but you won't have the carbon issue on the old longer plug.)

The brown boot shows you have the new design:

Originally Posted by cdynaco (Post 6636840)

A torque wrench is prob a good idea. After many years I've got the 'feel' for plugs but on aluminum heads I use a torque wrench.
Blow any sediment from the plug wells before you remove them so grit doesn't fall in the combustion chamber.
Double check the gap - don't trust the gap out of the box.

The 2008 Mustang Manual says to pull with a slight twisting motion for removing the coil on plugs. Recommends a bit of 'brake caliper grease' on the inside of the coil boots before installation. Tighten coil bolts to 44 lb-in/5 Nm.
It also says for "Late build vehicles" (Brown boot) to tighten plugs to 9 lb-ft/12 Nm. Silly book doesn't give the plug gap. It does for the 4.0L6 and the 5.4L 8, but not the 4.6L8. :screwy:

Originally Posted by texastboneking (Post 6636994)

If your going with an iridium or platinum plug do NOT try and gap them... they are pregapped and you risk knocking off platinum or iridium with the gapper... copper plugs you definitely need to check.

To the op. Copper will give you the most power/fuel economy but, will require replacement every 15-20k. But for 2-4 dollars a plug.. who cares :p

Originally Posted by muscledom (Post 6637012)

Have you heard anything about the E3s?

Originally Posted by texastboneking (Post 6637074)

Not really. The e3 was advertized more for lawn mowers if I remember right

Originally Posted by muscledom (Post 6637085)

Should I stick with OE?

Originally Posted by texastboneking (Post 6636994)

If your going with an iridium or platinum plug do NOT try and gap them... they are pregapped and you risk knocking off platinum or iridium with the gapper... copper plugs you definitely need to check.

Originally Posted by cdynaco (Post 6637125)

Thx! From the few sites I looked up it sounded like they were pre-gapped but none came out and actually said that. They did say the stock motorcraft SP509 were copper with platinum tip.