On a step v bottom I saw for every 100 lbs we took out, 1 mph gain roughly. at 4000lbs boat 29 v bottom would run 88mph. at 4800 lbs boat would run 81 or so. This was with a stock 500 hp efi.

You know the funny thing with my 29 Kryptonite, it ran the same speed and handled better with 2-4 people and a full load of fuel than one person and light on fuel.

That isnt the case with mine. It handles better with 4 people and a full tank of fuel, but top end is down 5 mph from what it is with 2 people and almost empty fuel.

The boat only weighs 4500lbs rigged. Throw 700lbs of people and 600lbs of fuel in it and it will definitely slow down.

On planing boats, speed = sqrt( hp/wt ) x C

Therefore, they have the same relationship: cutting the weight in half is the same as doubling the HP, doing either will increase your boat's speed by 1.4 times.

The cost of doubling HP is pretty easy to determine, because many around here build motors and have them for sale in the classified.

The cost of cutting the weight of a boat in half is a lot harder to determine. You may find that its cheaper to build a one-off all carbon/nomex race boat than it is to buy a production polyester boat.

A very light boat won't have all the stuff that a production boat has: no ice box, no carpet, no cabin, no stripper pole, ...

What kind of water do you plan on running in? Are you just loooking to go fast with the least amount of power and be comfortable on top of that?

Light, efficient, fast hulls always have trade-offs so it really depends what you want out of it.

Thats some funny chit right there!

So true. Light boat will beat the crap out of you in a wake.

My boat has a lot of power and runs close to 90 mph which seems to be slow by todays standards but in rough water I can, and have, walked away from 100 mph boats of similar size. When we get back to the dock they start spreading rumors that my boat is faster than I say it is.

The other comments I get when it gets rough are things like; "Man, you were really rolling.", my answer; "I wasn't going any faster, you were just going slower."

It's not how fast you can go but how long you can go fast.

Also, a hull that has more steps, doesn't make it more efficient than a hull with fewer steps.