i recently put a 358 roller motor in my 87 iroc and i used the 305 tpi set up and harness and motor pings realy bad and isnt making the power that it should the knock sensor is hooked up but timing is andvance about 15 degrees because of the came i want to know if that is a computer problemdo i need 2 have a new chip burned and also what psi are the stock 305 injectors