I am rebuilding a 1987 24 foot Baja Sport. The boat weighs about 4500 pounds. I am building a 540 that i expect to be between 700 to 900 HP. My question is about the outdrive in particular the gear ratio. Do I need to stick with the 1:50 ratio? What advantages or disadvantages would going lower or higher have. Your opinons would be a big help in educating me. Thanks

If you were 700-750 hp, then stick with a 1.5. More than that and you will have more prop options with a 1.36.

I guess a 1:25 would be going too far my application?

You definately won't need a 1.25.

BTW, That hull was never designed to handle the speeds with that much power. You better have full hyd steering and K planes to even attempt it.

I'd stick with a 1.50,its rare for a single to even pull a 32 pitch so I doubt you'll run out of gear,I haven't yet,Smitty

Thanks for the input. I have never built a boat like this and I am trying to eductae myself as I go along. The info is greatly appreciated and helpful.

700 to 900 hp is a world of difference. Dont think you will see 900 hp from a 540 unless you go forced induction. As`was said, tabs, steering, drive first.. then build power.