I have a true duel exhaust system on my 89 K5, 350 TBI. It is 2 1/2in. pipe into some cheapy Raptor mufflers. My problem is after driving about 10 miles, my SES light comes on. Its a EGR code that is triggered from insufficent back pressure resulting from the Duel exhaust. Anyone have a procedure to "fool" the ECM to prevent the SES light from coming on? I dont really want to remove the EGR, just trick evrything into working ok and not trip the SES. Thanks for you help in advance.