ok around 2100 - 2300 rpms my header sounds like an electric saw cuting through a 2x4 its a dc sports ceramic header yes i know there is better but i have an h23, anyways it really pisses me off because, 1 i hae rattles expecially loud ones, and second my crusing speed in the city is aroun that rpm so i hear it all the time. any help or advice woud be apreciated.

One more thing i noticed when i press the throttle and look down at the header it shakes like 1/10 an inch during that sound then gets steady again this is at where the heder conects to the down pipe but the bolts seem tight

 

are you positive that sound is coming from the header and not
the exhaust rubbing a heatshield anywhere or a piece of metal somewhere?
when you say you looked at the header and it shaked when you gave it
some throttle, were you sure this wasn't the whole engine moving?

 

No ive gone over the heat shield and its not that ie used a screw driver to wedge it away from the header and it still does it and vise versa away from the other stuff as well its not a heat shield and um engines alllways virbrate but then again it may but its only at hat point in the RPM band if it was a mount i belive i would have the shaking all over so.... that leaves me where i was before

 

could trhis be the problem??

 

It could be... try removing that whole bracket from the motor and see if it goes away.

 

I had the same problem with a DC (Stainless). Turned out to be the flex joint. It was just about impossible to find because I couldn't get the rattle to happen with the car up in the air or even sitting still. I finally wrapped some header heat wrap around the flex joint and it went away. DC replaced it under warranty. Apparently they've had this happen before.