so what's the deal with capping the resonator? does it create more power what let me in on the secret....

It is suppose to give you more turbo whistle. I blocked mine and didn't notice any increase. But for $2 its worth a try for many.

Tyler
MPF

Here's the secret. The resonator has been known to separate at it's molding seams, allowing unfiltered air into the turbo, potentially causing catastrophic damage. Capping it off is cheap ($3) insurance against that. Some, myself included, have noticed a different whistle after capping, some have not. Some have noticed quicker spool-up of the turbo, some, myself included, have not. You can even reinstall your resonator over certain styles of caps, giving it a stock look. Secret revealed!