Did Parts Store Give Me Wrong L67 Spark Plugs?

[ELECTRICxWIZARDx]

First, yes I did search previous threads, but found much conflicting info/opinions.

'01 GTP, bone stock. 151k miles.

Car currently has ACDelco 41-101 Iridiums installed. https://www.summitracing.com/parts/ado-41-101

O'Reillys dude sent me with ACDelco Professional 41-902 https://www.summitracing.com/parts/ado-41-902

Owner's Manual says OE spec calls for NGK Type PTR4B-15 https://www.summitracing.com/parts/ngk-5146

I even went back in to double check, I didn't remember the part number for the iridiums offhand, but knew it didn't sound right.


Now, from what I've read, plat plugs don't agree with waste-spark ignition systems, or forced induction. Check, and check.

So, go ahead and install the double plats i have, or go return them for the 41-101s, or something else you guys recommend?

[Fivefingerdeathpunch]

Th 41-902's are a factory plug for GM cars but not one I would run in a 3800.

Stick with the 41-101's.

[ELECTRICxWIZARDx]

Thanks, good to know. Durka Durka.

[SgtMarshal]

oooh durka durka durka muhommed jihad

[mguzzo]

stock plugs are PTR-4B which are platinum. Even stock you can safely run a TR55ix and it will work fantastic.
IMHO if you drive like its a stock car and don't beat on it, plugs don't matter, use a recommended cross reference to stock.
if you start modding then plugs start to matter.

[ELECTRICxWIZARDx]

IMHO if you drive like its a stock car and don't beat on it

I try to, but easier said than done. Usually end up getting into the boost once or twice on a 15mi drive into town. That sweet sweet blower whine is addictive.

Anyway, went ahead and returned the plats for 41-101s this morning. Judging by the condition of the old ones, motor seems pretty happy with them. Now just waiting for a new coupler to come in to get rid of the rattle at idle.

Off topic, but whats a normal idle rpm range? Mine starts around @ 1300, then settles down to 1k-1100 after a few seconds. But, also found a few worn vacuum fittings while i was in there, gonna finish tracing vac leaks tomorrow.

[Fivefingerdeathpunch]

It's coolant temp dependent of idle rpm, the colder the temp the higher the revs.

1300 on cold start sounds normal and then slowly down to 1000ish but once you are over 80-100 degree coolant temps it should be way down to around 750.