MSD Modular V-8 Coil-on-Plug Ignition Coil Review
Replacement of ignition coils on the 4.6L and 5.4L V-8 engines is relatively straight forward - unplug the connector, remove the single retaining bolt, then remove the plug from the spark plug. Reinstallation is reverse, and the coils are not nearly as difficult to access as the spark plugs they feed.
MSD's COP set for our 4.6L V-8 ran us just over $350 USD. At time of publishing, a set of OEM replacement coils from Motorcraft were roughly $335, so price is not a major factor in this comparison. The big question is whether or not the coils from MSD outshine the factory units. Since we're looking at the possibility of very small overall performance improvements the results are relatively subjective without the assistance of a dynamometer, which most of us don't have access to.
Another problem with testing and comparing ignition coils is that most of us are going to replace old, tired, and possibly failed ignition coils with brand new ones - of course you'll notice a difference in performance characteristics. For the sake of fairness, we replaced our tired OEM coils with the set from MSD. After a few thousand miles of driving, we then installed a brand new set of OEM Motorcraft COPs. The results, in short, are that there were not any noticeable differences between the two products. Based on our evaluation, both products performed adequately and we're comfortable suggesting that both products are inherently built with quality in mind. No measurable improvements in fuel economy were recorded after installing the MSD ignition coils.
• Quality OEM replacement
• Did not experience noticeable improvements
• Rubber insulating boots tend to disconnect from coils during removal (they can be easily reinstalled)
If you're looking for an alternative to the OEM ignition coils, the COPs from MSD are worthy products. Don't expect noticeable improvements or changes.
Long term update - 50,000 miles and several years on MSD ignition coils and no signs of trouble.