Spark Plug Gap on AC Delco 41 110 Irradium Plugs.

[Z34LS1]

O.K. so I searched through the Forums and find Gaps of .045 to .06
Seems Gap is related to Add ons....
My car is Stock other than True Duals, Cold Air Intake and the Tune that's going to Happen Tomorrow.

I have New 9mm Wires and New 41 110 Spark Plugs to Install tonight.
Setting the Gap seems to be a non Science after Reading Here.

The 41 110's I bought are all Gapped at .04 I'm going top run them there.

I found this online:

SPARK PLUG. Glow) Spark Ignition. . This fits your Chevrolet Camaro. Stock Code 12621258 Fitment Notes Pack of 8. Your Price $ 78.08 Installation Instructions N/A Additional Notes Alternate Stock Code 12571164; 12609877; 41-110; 41110; SEEPCN Categories Electronics, Charging, Wiring and Ignition > Spark Plug Assemblies Manufacturer GM

Quantity to add Ask A Question About This Product

Product Assemblies Image Name Description Product Application Notes NORMAL MAINTENANCE REPLACEMENT PARTS (LS1/5.7G); LS1 - ENGINE GAS, 8 CYL, 5.7L, SFI, ALUMINUM ENGINE; M30 - TRANSMISSION,AUTOMATIC 4 SPEED,4L60E,ELECTRONIC; PLEASE REFER TO YOUR OWNER MANUAL FOR (NORMAL)SCHEDULED MAINTENANCE PARTS; SPARK PLUG,(GAP 0.040)(DO NOT CHANGE SPARK PLUG GAP FROM .040)(ACDelco #41-110)(IRIDIUM). SPARK PLUG, Engine Tune-up(Spark,Glow). For: F 5.7G(LS1) (1998-2002) (1998 - 2002). Required: 08

[Z34LS1]

Previous owner had installed Bosch R3 Platinum 2 Plugs. These were Dual Electrode Plugs, 2 of the Plugs, Bank 2 and Bank 6 1 of the Electrodes were touching the Platinum. Unreal, can't wait to get the new plugs in.

- - - Updated - - -

Previous owner had installed Bosch R3 Platinum 2 Plugs. These were Dual Electrode Plugs, 2 of the Plugs, Bank 2 and Bank 6 1 of the Electrodes were touching the Platinum. Unreal, can't wait to get the new plugs in.

[cammed goat]

I would go with .45. I had my NGKs gapped at .40 in my old motor and it was cammed/tuned.

I have also heard of the Bosch Platinums contacting the piston and closing up. Scary.

[2002ssslp]

Previous owner had installed Bosch R3 Platinum 2 Plugs. These were Dual Electrode Plugs, 2 of the Plugs, Bank 2 and Bank 6 1 of the Electrodes were touching the Platinum. Unreal, can't wait to get the new plugs in.

- - - Updated - - -

Previous owner had installed Bosch R3 Platinum 2 Plugs. These were Dual Electrode Plugs, 2 of the Plugs, Bank 2 and Bank 6 1 of the Electrodes were touching the Platinum. Unreal, can't wait to get the new plugs in.

Bosch plugs are crap. I have used them in the past and have never had a good experience with them. I use NGK Iridium plugs in my 2002 SS and I set mine at .045 and they work great.

[Z34LS1]

Thanks for the Heads up, I may be pulling them back out and increasing the gap.
My Friend Tunes for Lingenfelter Performance Incorporated here locally, we'll see what he says tonight.
I noticed Last night when cold my car ran a little rougher than before, once the ECM takes control it ran really good!

I'd like to give a Shout out to Old #8..... F*@$ You you Bas$%#@@ Ass son of a Bit%^#^ my Popeye arms are all scratched up because of You!

[Z34LS1]

Got my 5.3 LSX in the avalanche a street tune, gonna do a mileage run tonight.
The Lumina was having a problem connecting to the data cable to the PCM. We were able to record two data logs showing fuel curves and such but not able to save the current file or upload through the odb2 port. So my puter got yanked and taken to LPI to do the tune.

Gonna be a couple days before I get it finished.
We also talked about Gap. Brent has tuned and and ran the Dyno for over 10 years, he said the .005 difference is so minimal it wouldn't show up on the Dyno.

Thanks for the Replies guys, .04 to .045 for Irradiums is perfect for stock to mild built motors, he said that on blown set ups they run a tighter gap because of air pressures.

[Redrokit8]

If I'm not mistaken, they come gaped at 45. Last time I used them every plug checked perfect right out of the box.

[Z34LS1]

If I'm not mistaken, they come gaped at 45. Last time I used them every plug checked perfect right out of the box.

Maybe Yours did but my brand new AC Delco's were set at .035 which baffled me.

Waiting on the Tuner now so I fixed a lot of stuff:

Leaky PCV Rubber had rotted, made new Aluminum Sleeve and lightly pressed the broken end into the aluminum sealed with light layer of RTV Black



And being to tight for egr block offs I made these...


Found this bad leaky hose way back on top by #7(Shown part way removed Dry Rotted and Cracked:


Should be way better now..........

[JayTA98]

Yeah I have to agree with OP on checking the gaps of brand new plugs. I had found some out of gap right out of the box.

[cammed goat]

By nature I have checked the gaps of plugs I installed in my previous cars.

[Smittro]

I use A/C irridiums in all my engines. Never an issue.

.035 almost sounds like a 6cyl gap..

[Z34LS1]

I use A/C irridiums in all my engines. Never an issue.

.035 almost sounds like a 6cyl gap..

I hear you, but it was a Sealed 8 pack...

[Z34LS1]

I read that these plugs should not be regapped, and if off return them for correct gap.
I can see why but if you have a gapper that bends the contact back without touching the Irradium Tip I can't see why you can't change them. My gapper works this way . The ones that slide between them then twist could Definately break the Irradium.

[Smittro]

I read that these plugs should not be regapped, and if off return them for correct gap.
I can see why but if you have a gapper that bends the contact back without touching the Irradium Tip I can't see why you can't change them. My gapper works this way . The ones that slide between them then twist could Definately break the Irradium.

Same one I use, I regapped mine all the time never had any problems.

Some sets have a spark patch added to the ground electrode and I could see where it could be damaged if not carefull.

But as I was saying, if you're carefull and use the right gaping tool you'll be fine.

[bryceslu]

The gaps would be different depending on what kind of plugs you are using. the .040 gap is for iridium plugs. Copper/platinum plugs would be a higher gap, I believe GM specced .060

There was a GM service bulletin put out years ago when they switched over to iridium plugs.

[Z34LS1]

The gaps would be different depending on what kind of plugs you are using. the .040 gap is for iridium plugs. Copper/platinum plugs would be a higher gap, I believe GM specced .060

There was a GM service bulletin put out years ago when they switched over to iridium plugs.

I posted the Bullitin above, unless there is an Upadate I believe it is .035

Got my Long Tubes on, waiting for the exhaust shop to get an opening to make a new Y Pipe.

[herculesrider1]

When the GM service manual says "Do Not Change gap from .040", I think I would follow their advice!!!! I just called Advance Auto, and they can't even order the AC Delco 41-110 Iridium plugs. All they had was NGK, Denso, Bosch, Autolite. So I called a GM dealership and they had them in stock but wanted $9.36ea for them...MAN, they are proud of them aren't they???? Then I called AutoZone and they had them in stock and only wanted $6.99ea for the same plugs!!! Do your homework and you can save money!....

[pajeff02]

I just swapped the plugs out in our Suburban -- the gap was already at .040" and that was the correct spec per the service manual. I did find that the plug number has been superseded from the number set forth in the service manual. Originally, these were 41-985's and are now 41-110's (exact same plug apparently). The stock plugs have 85,000 miles on them and actually looked about the same as the new ones from a wear perspective. Pretty amazing.

[herculesrider1]

I have heard that it is advisable to use anti-sieze on the plug threads and then dielectric grease on the coil/plug connections. Sounds like a good maintenance tip, but will the anti-sieze on the plug threads get down into the combustion chamber?

[cammed goat]

To be honest, I don't like anti-seize. Over time, that stuff solidifies and I have seen wheel studs lose threads from using it. But that's just me. I DO agree on the dialectric grease.