Whats the best sparkplug ?

what is the best sparkplug for a 4.8 --5.3 ,2000 silverado?

Factory recommended stock!

Chevy spends millions testing engines, unless you plan on creating your own testing department, just buy recommended stock equipment.

if you want to spen the money but they are well worth it i would go with the Denso Iridium spark plugs. I put them in my 2000 siv with the 4.3. you will also never have to buy or worry about buying spark plugs agian. thay are how ever about 12.50 a pop.

I used the Bosch +2 platinum plugs, I noticed crisper acceleration and better gas mileage.
-Jimmy

THE ABSOLUTE BEST SPARK FOR THE MOST POWER is a NGK TR55 and dont gap to full factory specs you want it a little closer

Factory recommended stock!

Chevy spends millions testing engines, unless you plan on creating your own testing department, just buy recommended stock equipment.
Actually chevy doesnt like to spend millions thats why they give you the most efficient spark plug from the factory instead of the most power giving!!! They recomend copper

Actually they don't give you copper. "Most" NBS 99-04 motors came factory equiped with iridium plugs. They last up to 100,000 miles (That I don't believe though) I changed mine at 85,000 miles and saw an increase in my fuel economy almost immediately. I still agree that if it came factory with those plugs they're the ones to use.

Actually they don't give you copper. "Most" NBS 99-04 motors came factory equiped with iridium plugs. They last up to 100,000 miles (That I don't believe though) I changed mine at 85,000 miles and saw an increase in my fuel economy almost immediately. I still agree that if it came factory with those plugs they're the ones to use.

What plugs did you put on? I've been thinking about changing the plugs when I finally get around to putting on a set of headers.

denso irduim, 12 bucks a pop but pays for its self on gas and performance

I used the AC Delco Irium plugs. Expensive but imho they are worth it

irduim is the best

i put nkg irduim in my truck with new 7.5 mm wires and i could tell a great change in the gas and preformance after i did this