I built similar engine for a customer about 12 years ago. It was for his 24' Sea Ray Sundeck with a bravo 3 dual prop, so it needed massive torque and to idle at low rpm. We did the gen VI block, 9:1 compression, 088 heads, rpm air gap intake and stainless marine exhaust with captains call. The cam we used was a comp 284HR with 230/236 duration and .547" lift, 112 lsa. It made over 550 hp at 5200 rpm, idled at 650 rpm with no reversion. Don't remember for sure but I believe peak torque was around 4000 rpm. That engine still is running great with many hours on it. Lot of people have been surprised by that tub of a Sea Ray. It runs a consistent 65 mph.

Bob Lloyd