Bought a demon few weeks ago with a pretty healthy 416. Car ran a best of 11.40 but seemed sluggish and slow to Rev to me compared to a very similar 408 I have with less cam in another car. Long story short had to change Trans and when pulled exhaust apart found these. Obviously removed them now car feels like it should rips to 6500 shift. Why would someone install these,
View attachment 1715910911 and any guess on et without?