Great response Bill- thanks for taking the time to write that all out. Just the kind of analysis I need to do.
I couldnt get the boatdiesel link to work but if the 6bt make that kind of power then the only gas equivalent is the big block (8.1 or 454) which, from every performance curve I have seen, should be making about 200 hp and just over 400 lbft of torque at around 3000-3200. I dont want to have to cruise a gasser any higher than that- just too much IMO. Its surprising how flat the torque curves are on modern gas v8's (see here- not marine specific but its a big block at least- Graph of 8.1L Factory Dyno - Diesel Place : Chevrolet and GMC Diesel Truck Forums ).
1) Can you fix that link? I tried and cant find it.
2) where can I get that 6bt for under 20? I am not above a reman or used engine but would prefer a reman obviously..
3) transmission seems like it needs to be decided on after the engine is found (while being considered all along of course) but the goal would be to turn the biggest prop as slow as possible. I have no idea what prop will fit on a Sisu but I think 22 is within an inch or so.
I really would like to stay away from a Volvo as you stated. I got myself all excited over a number of boats with them but I have the opportunity to start fresh here and would really like to stay away from the volvo parts cost/delays if possible. My mother had a volvo car and the radiator took 3 weeks and cost almost $2k...add the word marine to the order and it doubles in my experience (like the work "wedding" in case any of you have recently married).