Bravo 3s run kinda hot. Plan on an XR upper while you are at it. I would try to like a different boat

A lot of the Formula family boats of that era are powered to run 50-55. You’ll need a lot more power to go 65. A 525 would be unique and may get you there if speed is all you are after.

I like the suggestion of spending the $ on a 280 with twin small blocks. It’s still a 52-55 mph boat though, but the that pair of bravo 3s will throw it up on plane with 14 people in it no issue.

Coming from a guy with a 25' bow rider and looking to gain more speed, these guys are on the $$$. Get another boat if that's what you're looking for speed wise.

You're going to sink a lot of $$ into that boat to gain 10 MPH.

If you're looking at an engine upgrade, are you buying new? If not, you might be buying someone else's headache. (like I did. 1 season on it, and now EVERYTHING has been replaced)

As noted, a 525 puts you on the verge of the Bravo's power limits. Have you looked into the price of an upgraded out drive? I think I saw the B3 also hits a wall at around 62 MPH? (hard to make it go faster. A Bravo 1 is more suited for speed)

Not trying to dash your dream, just being honest.

General rule of thumb is 20-25 HP per MPH gained for I/O,

Leave it be. Enjoy the stock 496 reliability. Use the $$ saved for gas and beer!

Use it for a season and then upgrade to a bigger or/and faster boat next season.

It will probably cost you 30k+ to see 65mph and the 50k boat you have will be worth 50k or less. Without stock power, a Formula 26BR will be hard to resell and most people looking at one are willing to pay a premium for bigger power.

Agree 100% in so many way's it's the biggest waist of time and money to try and make it a 65mph boat in terms of time lost on water, time spent with project, lost resale value, the prohibitive cost of project, headaches after done; just buy a boat that goes 65mph. Don't ruin a good cruising boat trying to make it a go-fast. Get yourself a 28ss or similar Donzi 28zxo, Sunsation mid cabin, etc. lots of choices out there.

Twin 6.2 280ss went a tick under 60.

https://www.boats.com/reviews/nothing-to-chance/

My early no arch 330ss went 60 with 330 MPIs.

They accelerate like crazy. Could probably go up in pitch if you aren’t loading it down.

Hard boat to push. We put a Whipple on one. 650hp on my dyno. Still just runs 70

Exactly, seems all these guys who want to haul people in an open bow boat and want to go fast in one never intended to.
They overlook the boats you mentioned, and hands down the West coast builders have had those two nailed forever with all their open bow and mid cabin offerings.
Nothing but on Havasu pretty much.

I have 2000 280br with twin 350s bravo 3s. We love it. It will do 58. Not a speed demon but good enough.