2003 H2 Question

[mdoyle]

I've got a 2003 also and based on past experience I always stick with the AC Delco OEM plugs from the dealer. On another truck (Chevy Duallie) I tried the Bosch Platnium and there was a noticable reduction in power.

Years ago I ran a car at the strip and we would swap out plugs for different heat ranges and read the insulators as part of our tuning along with jet changes, ect. The main thing I learned through that process is that different plugs will make a very measurable difference in performance.