I'm looking at a Sea Ray 280 SS that will need a repower over the off season. It has twin 5.7s in it now. What does anyone think about dropping in a set of Whipple charged 6.2 ltr (383cid) Black Scorpions? It certainly shouldn't be underpowered. I would think they should be good for 500Hp and 600ftlbs approximately. A 280 SS should be a ROCKET with that type of BBC power with SBC weight.

Alpha or Bravo outdrives?

Alphas

That is going to be your weak link.

I would stay with stock 350's and enjoy the boat.

There in lies the problem. I'm looking for a boat I can entertain friends and family on but will be FAST. I would love to have a Nor-Tech, Outer Limits or something like that but they don't offer much space for entertaining on. I realize that a 280SS will never be as fast as a Nor-Tech but I would be happy with 60-70 knots.

That is a big heavy boat, for what it would cost, you could buy an Outerlimits or Nortek. These hulls where designed to go fast. There is no telling what your boat would handle like at those speeds. Then throw in full hydraulic steering.

Save your money and enjoy the boat and use the money for gas.

Umm just an fyi, some of my family has a 280 ss bowrider with twin alphas, it will do 60 mph all day long I believe

speed is not a problem with alphas its the hp you put in front of them.

It has twin 260 HP 350 Mags,

should have been more specific

The Bravo drive was born after Mercury put 330hp 454 in front of the Alpha drive around 1987. That only lasted 2 years and they stopped for a reason. The Alpha can not handle the power of a mild 330Hp for factory warranty.

You might get away with it in a small light boat, IMO