Spark plugs

[Green 1364]

My brother has a 2002 Silverado 5.3 what is the best spark plug for power and fuel efficiency?

[nards444]

unless your getting into some high HP stuff, the regular old copper tops, champion, delcos are just fine. Spending money on fancy plugs for every day production engines is a waste of money. problem is regular production engines wont detonate the way they should to take advantage of multi prongs, platinum etc.

[00Silverado4x4]

AC Delco's tend to work the best in these LS engines. It's all I'd ever put in mine anyway.

 

Moving topic to Gen III and IV Small Block and Drivetrain

[Duelin]

OEM

[Black02Silverado]

Just stay with the plugs that are in it now with a new set and you will be good to go. I have had great luck with mine and I have 155k on mine now. Second set of plugs.

[PJB1972]

AC Delco's tend to work the best in these LS engines. It's all I'd ever put in mine anyway.

+1

[DwayneJ]

unless your getting into some high HP stuff, the regular old copper tops, champion, delcos are just fine. Spending money on fancy plugs for every day production engines is a waste of money. problem is regular production engines wont detonate the way they should to take advantage of multi prongs, platinum etc.

You pretty much have it backwards.

Use 100K mile platinum or iridiums for low maintenance daily drivers stock ones work great.

Use basic copper plugs for modified vehicles.

Multiple electrodes are a sales gimmick nothing more.

Platinum pucks and fine wire iridium electrodes tend to cause potentially damaging detonation in modified engines and platinum pucks can be prone to comeing loose in them.

[8.1HD/ALLISON]

Stick with stock delcos.

[newdude]

OEM ACDelco.

[Jsdirt]

I threw some NGK Lazer Iridiums in mine last year. Noticed their construction was identical in every way to the OEM 100k mile Delcos I removed. Changed them at 68k or so just to be safe. Was shocked to actually see anti-seize compound on the threads from the factory. Might have actually went 100k without sticking in the heads, but better safe than sorry.

 

Only time I've ever noticed an earth-shattering performance increase after installing spark plugs was in my '85 Monte - thing had the OEM plugs still in it after 200k+ miles HAHAHA! There was just a little nub for the center electrode - if I remember right, the gap was north of .095" .. Used to have to cheat on the emission test - was always over 2k ppm HC ... and the limit was 230ppm, LOL.

 

Felt like it had a new engine in it after that plug swap. Low end torque increased 50%, at least.

[eddietorn]

I've used AC Delcos, they're reliable. A buddy has OEM plugs still performing after 60k+ miles. I have mine checked every 30k miles to be sure they're good.