Can I swap 25" outboards with 30"
 

I know this is a nooby question...

My 30' boat has 25" yamaha outboards and I'm repowering.
It was running good with 25" motors, they are just old and tired.

Can I run 30" outboards without jack plates?

What would happen if I did?

What kind of problems might occur if any?
This is new to me.

Re: Can I swap 25" outboards with 30"
 

WS:
I don't think you'll be too happy with this set up. Even if you jack your motors up another 5"s, you'll be rasing your CG significantly.
If you mount them in the same position, you'll be burying the gearcases and propellers. This will result in slower top end speed and potentially quirky handling. Why go with 30"s when 20"s (preferable) and 25"s are better performance setups by far? The less gearcase you run through the water, the faster you'll be.
Regards,
Steve