lowering the vtec mainly just give it a smoother transition from low cam to high cam... .. if you get it right you won't feel that kick when vtec kicks in.... most people with NA will set it to 5500 rpms..

 

Speed4,

Is your check engine light on after you installed the test pipe?

Im want to take my cat off and replace it with a test pipe but im afraid my check engine light will come on even after reinstalling th eo2 sensor???