I ran that cam in my street/strip '71 Cuda 340 and thought it was quite mild on the street, had a 4200 conv and 4.30's in it though, maxed it at only 6300 on the track, worked well and made 365hp with stock CR and unported 2.02 heads, its nowhere near what you have so exactly how it would behave with ported Eddies and 420ci?...in a word "Tame" but a good choice with .629" w/1.6 rockers less a bit of lash etc., I'd go for it for what you want.