b18c1 swap with ITR cams on my brothers car. NO cat...a resonator..and a n1 muffler. For some reason it idles perfectly......but at soon as your on the gas......it makes the putting sound out of the exhaust like a wrx. feels sluggish compared to what it used to be but vtec still pulls. If timing was off.....would the car still idle perfect? IF the valves were bent....would the car still idle perfect too? ...........or could the car just sound like that due to having no cat?

 

with no cat you would have a raise in tone, it would sound naisily at worst. if you valves were bent you would notice on idle,check your timing, and fuel pressure

 

Make SURE the spark plug wires are in their correct positions on the distibutor. I had this same problem. Sounded like a WRX and a strong spell of gas. It means your car is KNOCK'g. Hope this helps