Ever since the headers and LS6 intake install, the car won't shift until it's about to hit the rev limiter. When it does this, a pinging noise begins right at around 6000RPM during WOT, and continues until it shifts.

What is this?

 

detonation

 

What could be some causes?

 

Have you done a good top engine cleaning lately? Couldn't hurt to try and remove any carbon buildup that could be causing it.

Seafoam or GM Top engine cleaner will do the trick.

 

how about some tuning.....might help you out.

 

Ditto. Just a lil adjustment to the high octane table via HPTuners will do the trick.

 

change the fuel filter! They tend to starve the engine of fuel when they get dirty!

 

Did that last week.

I've done everything short of changing the wires and tune.

 

Did you screw with the MAF?

 

Nope.

 

I haven't changed my fuel fliter for 22K miles was planning on doing tune up stuff every 30K
plugs
pvc
fuel fliter
clean air fliter
and other related
however my pinging started 22K miles ago when I installed those dam NGK TR55 plugs gapped at .50 was told it's too much spark power and try to lower the gap.

I think I'll go back to a stock AC Delco plug
Thanks for any good advice for the newbie