Spark Plugs: The Definitive Answer

[BlazayBlazerious]

I've read a number of old posts about plugs and from all of the input, came up with two conclusions. AC Delco platnums are the preferred plug for our Blazers and that those plugs should be gapped to .060.

....But then I went on the AC Delco website to get the part number and found these two parts for my vehicle (98-W).

P/N: 41-932 - SPARK PLUG, PLATINUM PLUG - GAP .054
P/N: 12 - SPARK PLUG, RAPIDFIRE PLUG - GAP .060

Okay, so which is it? I was sure about the standard non-rapidfire plats until I saw the .054. So do they need to be gapped or is that the right gap for that particular plug? It's got me all *fouled* up over here...heh.

[wolfox]

Platinum and Rapid Fire plugs are two different animals. The smaller electrode tips (Think platinum "buttons" spot welded to the ground electrode and to the very "point" of the center electrode) in the platinum/double platinum tips does not require as broad of a spark gap for quenching purposes and fires much, much "hotter" than the rapidfire in the engine using the same stock ignition. Hence the gap is smaller. Want to really make your ears bleed? Iridium Laser plugs in my engine application are gapped to .031" as compared to stock AC/Delcos @ .045". And how do they run on such an engine? We'll know as soon as my CPI parts arrive. I have bets that say it will run like a cat with it's arse on fire.

Edit: D-oh, I forgot your definitive answer. It's Yes. Both. (duck -n- run)

No seriously, both plugs meet you engine's application requirement. If it were me? I would go for the precious metal replacements. They wear better, stay in tollerances longer, and because of the thinner electrode surface area, fire stronger, especially at cold start where you need every edge against fouling in cold weather that's coming our way.

[BlazerBoyLT98]

Originally Posted by wolfox

Platinum and Rapid Fire plugs are two different animals. The small electrode in the platinum/double platinum tips does not require as broad of a spark gap for quenching purposes and fires much, much "hotter" than the rapidfire in the engine using the same stock ignition. Hence the gap is smaller. Want to really make your ears bleed? Iridium Laser plugs in my engine application are gapped to .031" as compared to stock AC/Delcos @ .045". And how do they run on such an engine? We'll know as soon as my CPI parts arrive. I have bets that say it will run like a cat with it's arse on fire.

That was an interesting mental picture! I bet it won't corner like a cat with it's arse on fire!

[wolfox]

Blazers corner like bricks on rollerskates. I am filled with fun metaphors!

[BlazerBoyLT98]

Try Edelbrock shocks, the ride sucks but corners awfully well! When I do my next plug change it will be with the plats

[BlazerLT]

Install the plats and gap them properly.

[mike1224]

Originally Posted by wolfox

Blazers corner like bricks on rollerskates. I am filled with fun metaphors!

ha ha ha, i'm picturing that now. off topic for a sec, i love this blazer forum, i'm always laughing with the things you all say. thanks for putting a smile on Disgruntled Mike's face

[BlazayBlazerious]

Originally Posted by BlazerLT

Install the plats and gap them properly.

Now LT, that's the whole reason for my post. If I get the platinums that come gapped at .054 do I need to gap them to .060? Wolfox says leave em alone. What do you say?

Thanks Wolfox. More so for the cat and the brick visuals, but answering my post was swell too.

[BlazerLT]

Originally Posted by BlazayBlazerious

Now LT, that's the whole reason for my post. If I get the platinums that come gapped at .054 do I need to gap them to .060? Wolfox says leave em alone. What do you say?

Thanks Wolfox. More so for the cat and the brick visuals, but answering my post was swell too.

They don't come pre-gapped.

you gap them to 0.054 like AC Delco tells you to.

[BlazayBlazerious]

Originally Posted by BlazerLT

They don't come pre-gapped.

you gap them to 0.054 like AC Delco tells you to.

I get it. Thanks LT.

[DINO55]

Originally Posted by BlazayBlazerious

I get it. Thanks LT.

I gapped my AC Delco Plat's At .060 and my 98 loves them like that.
17/18 city 22/24ish hwy

[BlazerLT]

Originally Posted by DINO55

I gapped my AC Delco Plat's At .060 and my 98 loves them like that.
17/18 city 22/24ish hwy

well, I would rather him use the problem gap than experiment.