Well after getting my headers through MattG, I got them put on today. The first thing I noticed was a high pitched sound coming from underneath the car. I drove it around for a bit just to play. Needless to say it pulls my ass through vtec, but from about 1,000-3,000rpms I get this somewhat high pitched farting sound. I'm hoping it is something simple as tighten the bolts and not a flex pipe that broke during shipment. Matt packed it real well so I don't know, I figure that piece needs to be pretty durable to flex. Other than that it pulls just like I expected it to.

 

Probably wasn't torqued down to spec and you have a slight leak.