Well take a look and see what plugs you have in there. They may already be NGK. I doubt that you would see any improvement with the TR55 but there is one sure way to satisfy your curiosity. Experimentation is a great way to learn and messing with stuff can be fun.

Enjoy

 

NGK makes ac delco plugs that come from the factory, Ive seen plugs pulled out of an 05 tahoe that on side said ac delco on the other NGK. The factory plugs are hotter that the tr6 or tr55. The popular choice for the fi crowd is tr6 , the benefit you will see from a colder plug with less gap is it will help keep temps and kr down. thats a good thing.

 

Soooooo if youre geting knock you can try closing your gap??

 

It depends on your setup I milled my heads .050 and raised compression well above stock. It helped me to keep it down, of course I tuned for it also. In a stock engine you shouldnt have to mess with gap unless FI.

I could be off and if I am I hope someone jumps in and corrects me but in a stock engine if your having kr you need to tune it out, has nothing to do with plugs.

 

How exactly do I tell if I have KR? I am completely green at this......

My stock temp that my truck runs at is 205. It has always been like that, even after the efans. From what I have read, this seemd high. So, a colder plug may help......

 

NGK TR55 gapped at 35 thou for N/A, TR6's for blown or sprayed on a more than regular basis still gapped at 35.

 

this link will help read them

https://ls1tech.com/forums/showthrea...spark+plug+gap

the search feature is a beautiful thing

 

I know search is good, but the topic was already started. I search alot......hehe

 

My stock plugs were TR55's.