If anyone has not changed out their plugs by 60k, it is a must. Did the swap yesterday and am truly shocked at the difference. Gapped to .035 and went with the NGK IX plugs. I am shocked at the amount of room under the hood as well as the markings on the valve covers, Very well thought out and a simple DIY. Takes a little time because you are working 16 plugs but only took 2 hours from pulling in the garage to cleaning up the tools. I am type A so I used a torque wrench on all the plugs. I am truly amazed at the noticeable difference. Now time to finnaly get to the headers.

 

Doing mine this week! Thanks for the gap recommendation wasn't sure about that as I have the same plugs. I have 78K on my beast with original plugs.

Just curious, can you explain the exact, even subtle differences with the new plugs? I know they'll be better, just wondering how the car sounds/feels/drives differently.

Thanks!

Alex

 

Idle is much smoother. Noticeable increase in throttle response, especially when stomped off the line. I am shocked at how much this minor swap increased performance. The plugs were original and I think with the increased boost of the S/C, they should be swapped at 50k max. Go to Sears and get the correct sized swivel spark plug socket and have a 17mm box wrench. I also applied Anti-Seize compound to make the next swap a little smoother.

 

I switched my plugs out at 20K

 

NGK-LFR7AIX Plugs are a must! Especially if you have any mods. Nice work!!

 

I have 16 in my hand now, so will try and get them installed today and post a mini-review like the one above.

This is one of those, "No brainer" mods that every E55 owner should do. This and an upgraded IC pump. (I have the Johnson version).

Can't wait!

Thanks again guys, this really helps me.

Alex

 

With all the goodies on your car, she will certainly scream even louder. Your performance upgrades looks like my shoping list. You will be surprised, I bet $$$$on that. Keep the shiny side up.

 

Got the IX in mine too, gapped them at .032 though. With 52K miles on my car, I have probably changed my plugs at least a handful of times already.

 

What did you torque them to? You could actually get a torque wrench on all of em? Any of em a pain to get at like perhaps passenger side rear? Those are usually the tough ones to get at on a lot of cars. You got em all from the top?

I know when I looked at it it seemed like there was a good amount of room, but I didn't look very closely yet. I'll probably do these in the next couple weeks. Wanna get the car running perfectly and reliably before I start any power mods.

 

I used a 3/8" torque wrench and had no problem getting to all of them. Used the swivel plug socket with a 3" extension on all plugs. I torqued them to 140 inch/lbs. The last plug, all the way in the back on the drivers side is the only one that is even a little tough, but not much. The beauty of the plug socket is the plug fits in nice and snug so you don't drop them either going in or taking out. Mine were at a 050 gap so you must gap. I went with .035 because that was the gap of the plugs I pulled. Do one side at a time and use a bungie cord to hold the air box out of the way. Lay all the coils up on the S/C and cover them with a towel. This way they do not slip down where you are working. I just numbered all the plug wires just in case.

 

Forgot, the plug wires were perfect. Very nice set and great quality for OEM. Not much resistance so I put in a little bit of dialectic grease into the boot and they were good to go. I don't mind spending money but I will not waste it either.

 

Wise man, could be why you are pulling eleven dead! Not an easy task.

 

I will gap mine at .032 then!

Thanks for the advice as always everyone.

Alex

 

I did mine earlier in the year and didn't realize how straight forward it is. Just have to make sure the plug snaps when back on he spark plug. If not might get a cel code or rough idle

 

Checked with Dyno Comp in Scottsdale and they'll only charge me 2 hours of labor for the install (I'm a complete idiot when it comes to mechanical things), which sound about right if I were to attempt a DIY. Should cost me about ~$200 for the install.

I'll do a quick video of me romping on it after the install and comment on any performance increase. No -160-0 MPH runs though. (Too hot in AZ right now anyway).

Can't wait!

 

Considering they are Aluminum cylinder heads and are probably stuck in there pretty well, it is probably a good move to have garage do them. I wish I was closer and could do it with you. Once you see a job done in person, you have no problem doing it the next time. I lived off Pima in Scottsdale back in 1994 across from Grey Hawk. Owned the car wash at 59th and Bell road. It is nice that you are so close to Mexico to do some of those 0-100+ pulls! Takes me a good 25 hours to get down there to test out my ride.

 

Are these the colder plugs?

 

just did mine few weeks ago.... i didn't mess with the gap i think they came pre-gaped and i installed them did the valve covers and fired her up... this is at 70k miles and man she idles as smooth as it could be.. nice response and i just drove it to Miami few days ago averaged 19.7mpg at one point i hit 20mpg lol doing about 80-90 80% of the time with the occasions of doing 140-60 ones or twice... it worth it

 

Good advice, thanks!

 

They are!

Alex

 

With your upgrades, your car will love a step colder. Look out!

 

What is the recommendation for us stock guys then...regular heat range NGK Irridiums?

Does anyone know the part number for these?

What if any negatives are there in running colder plugs on a stock motor?

 

Car is in the shop now and I'll do a quick video dropping the hammer with a 30 second review and post it here for you all to see. It's pretty hot right now in AZ so this won't be the insane bonzi run I did below in my sig, but a few 0-60MPH's whent he Po-Po aren't around.

 

NGK-LFR6A are stock. NGK-LFR6AIX are the same temp and are a better plug for a stock motor imho. NGK-LFR7AIX are a step colder and are great for boosted motors. A step colder plug on a stock motor won't hurt anything but you will also not get the full benefit of the plug.

 

Im at about 55k miles now and think I should change my plugs soon.. What about wires? Should I change those out as well or should I wait?