irridium spark plugs (Page 2/3)
sledcaddie FEB 20, 09:29 AM
While we're in the category of spark plugs, what are your thoughts/experience with using anti-seize on spark plug threads?
1985 Fiero GT FEB 20, 09:48 AM

quote
Originally posted by sledcaddie:

While we're in the category of spark plugs, what are your thoughts/experience with using anti-seize on spark plug threads?



Me and my dad always do, I haven't been into cars long enough to have to take out old spark plugs with anti seize, but it's a good precautionary thing to do.
Vintage-Nut FEB 20, 10:01 AM

quote
sledcaddie:
While we're in the category of spark plugs, what are your thoughts/experience with using anti-seize on spark plug threads?



Especially with aluminum heads!
1985 Fiero GT FEB 20, 10:05 AM

quote
Originally posted by 82-T/A [At Work]:
I can absolutely attest to this. Back over 15+ years ago when I used to drive my 87 SE/V6 regularly... it performed just as you said until I upgraded my ignition coil. I went with an Accel SuperCoil (or whatever it was called back then). Bright-yellow coil which I spray painted black to look stock. I noticed idle was slightly improved, but that could have just been plecebo. I didn't notice any power increase until around 4,500+ rpms. Essentially, the difference was that the engine continued to pull strong as it did in the mid-range, and it felt like I had more actually usable power in the upper RPMs than I did before. It clearly made a difference.

I've had a lot of people tell me this isn't so... maybe my stock coil was starting to go... but either way, your point about the 4cyl coil and the V6 coil is on point. The coil is basically a capacitor of sorts... and it simply cannot maintain / recharge quickly enough to provide that level of voltage to the spark plugs at the higher RPMs. There have actually been dyno tests that have shown this. I saved them somewhere, so maybe I'll make a page about it one day.


For both my daughter's car, and my car, we plan to use the MSD 6EFI system. In addition to the multiple spark discharge feature, it also provides a more complete burn to help eliminate carbon deposits from ever occurring... or at least not as frequently, and is supposed to smooth out idle. On her little 4 cyl, I doubt she'll ever see a power increase from it, but anything we can do to improve the efficiency of the motor will be useful. For me, it's about the learning opportunity with her. We'll rebuild and put everything back to stock, and then install that in an inconspicuous place along with the factory wiring to see if there's a change in idle and normal around-town driving.



My car's off the road for the winter, I'm working on it, and I replaced the ignition coil with the MSD stock size/location one, 50% higher volts, and red. I also got top of the line red spark plug wires, and regapped my plugs to .060 (4 cyl stock gap) to take advantage of the higher volts. As I haven't been able to drive it. I can't say anything about performance yet, but idle is smoother, and throttle response is better. That combined with ported exhaust manifolds, Rodney EGR tube, cleaned out PCV valve, and some other things have made my idle rock solid, much improved sound and throttle response. And should improve power and fuel economy.
Patrick FEB 20, 05:21 PM

quote
Originally posted by sledcaddie:

While we're in the category of spark plugs, what are your thoughts/experience with using anti-seize on spark plug threads?



Is there any reason not to?

I always apply anti-seize to sparkplug threads, and dielectric grease to the inside of the sparkplug cable boots (at both ends).
Stingray92 FEB 20, 10:18 PM
I had a gm piece of .... that every 40k would fracture the ceramic insulator on #1 cylinder. The TSB was a waste of time and even installing the high end plugs didn't fix my problem. Ignition is all about providing a source to ignite the fuel/air mixture. If you're building a performance motor go for it. I remember the v6 being a pain on the plugs if you're looking for a long lasting plug I think you're wasting $ on iridium or even the newer ruthenium.
82-T/A [At Work] FEB 21, 08:38 AM
I'm surprised GM didn't design some kind of dew strip to prevent water from going down the backside of the glass and onto the spark plug holes.

Oooh... that's right.
1985 Fiero GT FEB 21, 09:32 AM

quote
Originally posted by 82-T/A [At Work]:

I'm surprised GM didn't design some kind of dew strip to prevent water from going down the backside of the glass and onto the spark plug holes.

Oooh... that's right.



If I remember right they did, but even then it wasn't enough. It didn't stay sealed when the trunk was opened, which pours a ton of water down there, that is mainly what cracks that manifold and puts enough water in the plug holes to rust them out. I saw a design awhile back that was a sort of tarp, that connected between the trunk and the firewall, and funneled the water out the sides, onto the air box and battery, that's better for the hot engine.
87GT3800SC5SPD FEB 21, 03:40 PM

quote
Originally posted by 82-T/A [At Work]:

I'm surprised GM didn't design some kind of dew strip to prevent water from going down the backside of the glass and onto the spark plug holes.

Oooh... that's right.



They did, then later issued a recall to remove them.

Taking the deckled off makes more room to change the front spark plugs.

[This message has been edited by 87GT3800SC5SPD (edited 02-21-2024).]

theogre FEB 21, 04:21 PM
⚠️ No matter what plugs are installed, you need to check, clean or even replace them or have corrosion eats the "body" metal.

Example: i use AC or Autolite "Double Platinum" (because duke dis engine) that have coating to prevent rust but #1 plug still gets rust because close to right vent that allows "water" to getting to it. Results:
see https://www.fiero.nl/forum/...HTML/146263.html#p10

V6 & many Swaps have similar or worse problems when have "fire recall" done that removes the lid strip controlling rain & crap getting thru the window gap w/ the deck lid.

Any buildup will cause problems like look at #3 & 4 in link when "dirt" have remove the coating just above the cone & those plugs are "protected" by the air cleaner.
@ minimum check/clean the plug base even w/o removing them & remove rust/dirt around the plugs w/ small picks & compress/canned air.


------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

[This message has been edited by theogre (edited 02-22-2024).]