I'm new to the whole Cobra Mustang seen and I'm soon buying a 96-98 Cobra and I hear a lot of people talking about IMRC's. I have no clue as to what they are and what they do. All I know is it's something to do with the intake system somewhere. Can someone please help me out and tell me why everyone deletes them?
They're butterflies in the intake set to open at around 3600 rpm, essentially making the intake a two-stage. The idea was to raise torque at lower rpms and then open to shorten the runner for high-rpm HP. Some guys with blowers have removed them w/ the delete kit, the idea being increased airflow and a shorter air path. Recently I've heard that dyno testing reveals there is actually a power loss w/o them.
They actually open at 3250rpms, and they are actually located between the intake and the heads...IMRC stands for Intake Manifold Runner Control...Here's a picture of some really dirty ones from out of my car...I have since deleted the butterflies but I don't recommend it for anyone that's not blown or doesn't have a ported intake or heads...
