So what plugs are some of you guys running and whats beter NGK Iridium or Copper.

Thanks

bump

 

I'm running the BKR7E step colder coppers and my engine is running smooth. Just to keep it simple, the Iridiums merely last longer than the coppers; copper is the best heat conductor and I believe the Iridiums are copper cored with iridium on the electrode for longevity.

 

Copper is cheaper, and arguably a tiny bit better in high performance applications.
but Iridium, while more expensive, lasts alot longer.

I think either is good.

 

Do you have to gap the iridium spark plugs ?

 

Yes, you must always verify a proper gap.

 

you have to gap all plugs.
never trust the factory gap without checking.
also if your modded dont just assume a certain gap is right.
test a few different gap settings to find what your car likes.

 

how exactly do you determine what it likes, in my previous L61 I used gaps from .030 all the way to .045 and nothing ever seemed to change

 

Basically, go for the largest gap you can safely run with your car, before you begin to notice it doesnt like it.
things like a rougher running, rougher idle, spark blowout, sputters, misfiring, low down bogging etc etc.

F/I cars generally will need smaller gaps than N/A

IMO with these cars, start at 0.40
if it runs nicely there. use that.
if you notice any negative effects, drop down 0.02-0.03 at a time until it feels like the car is smooth.
Alot of guys with stage 2 or above like runnign 0.35.

 

It becomes more apparent when your particular car has either modifications or conditions it is put through that make adjusting gap from stock more crucial. Stock gap is optimal for gas mileage and emissions as well as power on a stock car. Say you go with the stage II; will it probably run okay with the stock plugs and gap (Assuming you run premium fuel), yeah it will although you could dial it in a little better for the situation. Now say you went to a 2.9" pulley, exhaust and an intake; at this point you would start running into a situation where the stock plug at stock gap cannot properly ignite the mixture. If you now install some step colder plugs and gap a little smaller than stock (Trying a few different gaps to see what works best) you would notice a smoother running engine that is able to provide the spark that is needed to get a full burn.

 

Thanks for answering my question ! +1 rep for you .

 

NGKs

 

has anyone tried the AC Delco irriduims yet?