I just want to ask this question because I haven't been able to get a good answer to satisfy my inquiry. Which plug works best in overall performance in the LS-based engines N/A. I have been seeing advertisments for E3 plugs and these Pulstar plugs. Are any of these any good. Anybody test them??? Or is all this just smoke and mirrors? I talked to a local performance shop and they suggested NGK TR55s. They work really well. Just don't last as long.

 

NGK TR55's, you have the options of coppers or iridium.

 

You cant beat the factory plugs as far as longevity goes. They seem to do the job as well.

 

Dude I havent felt a better smoother plug than A/C Delco 41-985 Iridium's! I run them in my truck & WS6! BTW I gapped mine at .045! Try them you wont be disaponted and you wont have to change them for a while a plus when you have longtubes

 

your not suppose to change the gap on them.

 

I Agree With Using The Ac Plugs They Work The Best From What I Have Seen

 

I picked up a set of bosch iridium plus 4 plugs at half price when a local pep boys went under. Believe me i'm leery of any new fangled product but at 50%off i'd try them. Installed them last weekend finally and definately noticed a smoother acceleration on my 6.0 vortec pickup. Inside the box is a moneyback gaurrantee coupon if one does not notice any difference send the reciept back for a full refund. So far so good as it runs smoother but too early to tell yet if my mileage got better. Dave

 

all that matters is they are iridum. the plus 4 is a gimmick as the flow will go to whichever post has the least resistence and the other three will chill not doin anything.

 

FWIW, I've had the factory platinums, Denso Iridiums, and NGK TR55's in my truck and I haven't felt a difference between any of them...not to mention that the stockers were gapped improperly (gaps ranged from .045 to .065).

 

I'll stick with the stockers. Can't go wrong with factory parts made to work like it is suppose to. I just wanted to see if anyone found a better plug for stock engines.