"It is true there is a discrepancy about what the gap should be - the GM
service manuals say something like .033" or so, and the owner's manual that
came with your car says the gap is supposed to be .028". Based on my
experience tuning turbocharged engines, I believe the .028" to be the
correct gap, and everybody I know that tried to run more than .028" with a
tune ended up with misfire problems."
"I don't believe the "results" people are posting about power, MPG,
drivabililty gains. I believe it all to be placebo.
Short answer: gap them to .028" and don't mess with it. Lol"
- Vince Geglia
Trifecta Performance, Inc.