except I run anti sieze on plugs.

 

Don't NGK TR-55's come pre gapped at .055?

 

Like I mentioned, for me if I leave them in for a while I start to notice a very slight decrease in idle quality. I know it's not a Cadillac, but when I change to fresh plugs and get a smooth idle again, I know that I'm doing the right thing. It's like there is a very very slight misfire, you can feel just a slight "bump" every 4 or 5 seconds. I know it's probably not slowing me down, but it still makes me feel better knowing I've always got relatively fresh plugs in my engine. And like I said, the longer I leave them in the harder they might be to take out later on.

I always go with the regular NGK copper plugs. I'd much rather go with a fresh set of those every 6 months instead of doing platinums or iridiums for longer intervals. It's kind of ironic, since I'm the guy who likes to go 8k or longer on my oil change intervals with synthetic oil.

 

The preset gap is actually closer to .059 according to NGK, while their TR5 comes in at .039. That is the only difference between the TR5 and TR55. They do this because it's recommended that you do not change the preset gap by more than .010, otherwise the ground to electrode relationship isn't as square anymore. So if you want to run a smaller gap than .050, you should go with TR5s. The TR6s also come in at .039, but are one step colder (great for nitrous or forced induction) Also be warned that TR6s will foul out faster than the stock heat range plugs. I ran TR6s in my 98 Formula and they fouled out in only 13k (I got a very bad power loss above 5000rpm that felt like the fuel pump was cutting off)

 

^ Thanks... since you change those plugs out so much what do you torque them to? Do you use a torque wrench or tighten them all the way by hand adn then go a 1/4 turn or someting more?

I changed the plugs once on my aunt's '98 vert and it was a bear for the #7 plug and I was so afraid of cross threading one.

Any tips? I'm getting my Z06 dyno-tuned in January and I want a fresh set of plugs in. I run HPDE's in the car and it runa a hair rich at WOT.

 

Yabba yabba yabba

Your dad owned a gas station, so that makes you a high-performance ignition expert.
But my dad's a minister, so I have divine insight!

A larger plug gap is NOT analogous to two plugs per cylinder.

I've spent considerable time on the phone with Jacobs and read their literature. I just haven't ever seen any racers that run their ignition. Nor have I ever seen anyone with an exceptionally fast car that had their ignition. Not to say that there isn't someone, somewhere. Also not saying it's bad stuff. Just that considering the huge benefits that Jacobs claims, it seems to be, uhmm, "under-recognized" by the hard-core performance community.

Multiple coils have been in common use for at least 25 years on motorcycles, and (coincidentally?) that's where I've had my worst misfire problems. Aftermarket hotter ignition was no help. Solved with a narrow gap, no reduction in ETs.

I've never said that a wider gap doesn't require more voltage. Only that lack of voltage isn't an issue for most of us, and more voltage isn't the cure for most misfires and plug fouling. A large gap is much better for firing lean mixtures, with the tradeoff that it is more misfire prone at high cylinder pressures, regardless of the voltage. I'll gladly sacrifice idle quality to be sure that it's hitting on all 8 at full throttle.

At this point I'll defer to MadBill
Go through his posts to date, and I think you'll see that he's a pretty smart guy. If you can stop leg-humping Jacobs long enough, you might learn something from him!

 

I just basically tighten them slightly snug, but I don't crank down on them too much. I've never had a plug back out on my yet, and they are always easy to remove the next time around.

As far as tips go, the plugs are pretty easy to do on these cars, just be sure to have a few different extensions in your socket set as some plugs work easier with longer extensions while some work better with a real short one. It helps to completely remove the plug wire from the coil too. None of the plugs are obstructed too much, so even if you take your time you can still get it done in well under an hour (as long as none of them are stuck in there that is)

 

Do you think you got an answer to your question or are you even more confused...
Why don't you contact the people that make the plug that you finally choose and ask them

 

I think I got my answer early in the thread and posted my course of action in a later post (#5); I also got a lot of good information and varied opinion which I think is also good. My original post mentioned the type of plugs I am going to install. Thanks to all that contributated.

 

I read that most, if not all, of the new long life plugs come with anti-seize compound already on the threads. It is supposed to be good for one installation. If you remove the plug, then you have to add your own anti-seize compound before you re-install. Is this true?

 

I never bother running antiseize on my plugs, I just put a few drops of regular motor oil on them. I have never had a plug stick on me in 20 years of changing plugs.

 

I haven't either, but then again this is the first car that I have owned with aluminum heads so I am more concerned about it.

 

I haven't heard of anyone having a problem from using anti-sieze on plug threads, but I've seen the grief from not using it, especially with aluminum heads!

The longer you are going to leave the plugs in, the more important it is too.

RonJ ...

 

Why don't you all read your owners manual, It will tell you what plug to
use and when to change it. my .02 cents.

 

Spark plugs are tight 1/16th past finger tight.