merlyn1965

I'd like to know how much power that I can send through a king cobra stern drive. I know, I don't have a mercruiser and I'm running some old equipment but that's what I have. I've build the 460 to around 420 HP and got the boat to 67 mph but the bug for speed did bit me hard so I'm looking to beefup the engine some more this winter. But then I'd like to know where I should stop cos it'd be a bummer to loose next boating season for a stern drice failure. I'm restricted by what is called a budget. (You know the thing that we're always blowing up)
Any info would be appreciated.
Josh

Airpacker

What year cobra drive? If its an early one with dog clutches, you are already on borrowed time. If its a later cone clutch type, you should be ok at 500hp if you're easy on it.

merlyn1965

It's an 87, 1.42 ratio.

Airpacker

you are already pushing it to its limits and then some.

merlyn1965

What should I change? The upper or the lower? And thanks for the info.

Airpacker

The weak point is the lower. Its really a 300hp outboard gear set with dog clutches. Not ideal to take the torque of a Big block. I broke 13 drives in 2 seasons( blew gear sets and cases_) before giving up and trading boats for a bravo equipped unit. I only ran 450hp thru the KC drive and couldn't make one last on a 22 foot v hull.