So I have a 93 civic si with a p28 chipped ecu (bought it that way) and vtec engages at 4500(only has aem cam gears and intake and exhaust, stock mani) and I really don't feel a boost of power compared to my old gsr eg I use to have when vtec kicked at 5300.

Should I trade for a stock p28 and then have it chipped and tuned or would a stock ecu just slow the car down?

Help appreciated.

 

The program your "chipped" ecu has is probably some garbage ebay chip that runs rich as hell & throws needless amounts of timing into your motor.

Your ecu is probably socketed.
To check watch the video on how to remove/install an eprom chip listed on http://phearable.net/tech

If it is, you can simply install another chip with a proper map for your motor/setup.