Has anyone used the iridium plugs available for the 5.4L 3 valve yet? I had a plug burn off the ground strap and electrode the other day, so decided to go ahead and replace all 8 along with the coils and injectors. I'm going to put the iridium plugs in with MSD coils and 4 hole injectors. Anybody done this yet?

 

I didn't know there were iridiums out for the extended reach plugs...Unless you have the standard plugs that are on the revised heads?

 

I think they're new to the market. Here's the link to them.

 

hmmm never heard of the brand. Honestly, I'd just stick with the MC ones and change every 60k.

 

As soon as Motorcraft comes out with an iridium plug, I'll use them.

They're not that difficult to change, if I don't like them, I'll pop them back out and replace them. I just replaced them with stock, 5k miles ago and already had one that blew apart on me. Time will tell.

 

I looked at those too, but went with the platinum. You wouldn't get much better or longer performance.

I stay away from those coils, buy motorcraft and save yourself a future headache. Are they bad? How many miles on them? If still good, just do boots and springs. My coils have 117k and still work great.

 

Yeah, they're bad. 254k on them now. I've already lost 2 of them in the last 6 months. I'm after fuel mileage mainly. I'm upgrading to the 4 hole injectors at the same time as plugs and coils, so we'll see what happens. Mine is early 07 with the 2 hole injectors. If the MSD coils don't last, I'll pull them and put the 511s back in. The only reason I entertained the idea of non-stock coils is because they're MSDs. I've used a lot of MSD products through the years and never had any complaints. We even had 2 MSD distributors on our 2100 hp blown Aries pulling truck. They've always made a good product as far as I'm concerned. I'll post updates after I get them in and we'll see if they make a difference or not.

 

@bhunt3450 MSD was bought by Holley in the last year, so I'd be suspect on the quality of them now. I bought my MSD coils back in Dec 2017, and they were installed March 2018. I've got about 16-18,000 miles on mine so far.

 

I didn't know Holley bought MSD. Been out of the hi-po game for a while now. Hopefully, they let the MSD people do what they've always done. I had a spread bore Holley on a 383 stroker years ago. Had to mess with the jets at least once a week. Sounds like you're getting along with your coils pretty well. Did you notice any difference when you put the coils on?

 

Nope, no difference in power, acceleration or fuel economy.