I have a 2003 TL TYPE S and inside my intake manifold it has the IMRC.
does anyone know what this IMRC does and how it works exactly?

 

anyone know?

 

It lengthens and equalizes sides.

 

sounds like chevys old `TPI` tuned port injection, where the runners were all equal length to maximize engine performance- doing it how it should be done~

 

i want to build a custom intake manifold but i need to know as much as possible about this runner control. So i was also wondering does it open at a certain rpm range? How would it affect the engine and drivability if you put on the old j32a1 manifold that does not have the IMRC on the j32a2?

 

My guess is you would lose high-end power. Test it out, just disconnect the power to the bypass valve actuator and take the car for a spirited ride. You'll notice it when you get up high in the rpms.