[SpiritOne]

Well it all depends on what type of outdrive you are looking at, how big the engine driving it is, and how big a boat you want to push. All of these factors will affect your gallon/per hour fuel consumption.

Really, between comparable outdrives, the Penta and Mercruiser are both very good drive units. Both can be serviced just about anywhere you go, and both will get your boat where you need to go.

I am more familiar with Mercruiser simply because thats what I have on my Crownline. I have a 192Bowrider with a 220HP 5.0L engine and the Alpha Mercruiser outdrive. Single Prop. For a 20' boat, I can cruise at 30-35, and use a moderate amount of fuel. My top end is around 53-54 depending on drag and the water (note this is with a 21 pitch prop).

There are two types of Mercruiser Bravo outdrives, the Bravo 1 and the Bravo 3. Both have 2 props on them that counter-rotate, they give an insane amount of hole-shot speed (hole-shot is defined at take off speed, or off the line speed) and increase your top end by quite a bit too. They usually are mated to higher end engines though, and thus use up quite a bit more fuel. The original Bravo 1 has heat issues, so I would stay clear of it, it requires you to install a drive sprayer, a device that sprays water on to the top of the drive unit to help keep it cool. The Bravo 3 however runs cooler than my Alpha outdrive and is exceptionally efficient.

The Volvo Penta has several outdrive offerings as well, including a dual prop counter-rotating design just like the Mercruiser, but I have not heard of any heat issues with any version of theirs.

Which ever one you decide to go with, just remember than your outdrive choice is just one of many decisions that will effect your boats performance. You have your engine size, boat size, prop pitch, prop type (aluminum or Stainless, stainless is better but more expensive), and outdrive configuration (single prop or two).

does any of this help, or just confuse you more?