Id throw the 620 away from the dyno tests ive seen from it. The .620 has to tight a lobe center for a stroker like that. Id probably pick a hughes 268/272 630, lift on a 108 cl or their 272/276 650 lift on a 108 cl

Or you could go with a comp grind SQ lobe 7265/7265 witch is 271 @ .050 with 603 lift on whatever cl you want, for me a 108to110 or you could pick any other cam around the same perimeter IMO