20 Bahia power

[dcasey10]

I love the 20 Bahia. Keeping an eye out for a 4.3 block on craigslist to maybe fix my cracked 2006 vortec. i splashed it this weekend and it actually ran amazing, did almost 40 mph.

Considering the cost of getting a nice new block and rebuilding cost I was thinking about just putting in another engine (used and at cheap cost, craigslist is amazing), such as a 3.0 volvo or 350 merc or even..... a 454..... Straight pipes out the back oh baby. Would a 454 fit with out major work? Would the extra weight not be worth the bump in power? the 4.3 is perfect with 225hp and 670lbs vs 350 300hp, 950 lbs, 454 320-350hp at 1200lbs

Or will one of you just buy this thing before I turn it into a donzi!!

[coolair]

Go to a junk yard a pick up a block. I have a 4.3 bare block at my office, I think the cam is still in it. But I don't think its a vortec.

[Rocket]

The weight aft in a 20 in not a big problem unless you don't like the look of it sitting aft down at rest. With the power once it is up and running the 20 handles very well with the weight aft, re entering the water very softly drive first. I have a small block putting out 320 hp running through a Volvo xdp duoprop in a baron and very happy with that combo, although I have my eye on the new 6 litre 430 hp Volvo, but it aint gonna happen.

[dcasey10]

Rocket,

by small block you mean a 350 v8 block (possibly bored out or tuned for the 320hp I bet)

What does it do for speed and fuel consumption?

[Rocket]

Yes, 5.7 litre. I have the F7 props I can only get 4900 rpm at WOT, so I am a tad overpropped, but I get 51 Knots (62 mph) top speed. If I cruise at 4,200 RPM, I get 42 Knots and burn about 10 gph, so the fuel economy is really exceptional. This is an engine with electronic ignition I have really had not trouble with it except when the engine is warm, in hot weather it will stall when first re-started unless you add throttle for the first 5 to 10 seconds. I suspect my boat is lighter than a Bahia Mar, the bottom is very fair with no bottom paint and the low profile would have lower wind resistance.

[ianupton]

I do not think a 3.0 is enough. I do not quite have the speed need that Rocket has, but I like to zoom along at a good clip.

I agree with everything that Rocket says, but I am one who really doesn't like the heavy squatting with a V8 in the stern. I think the V6 is a perfect compromise.

V6 (220 - 225 hp) with a Duoprop or Bravo III will give you 50 mph. The times that you can truely run that fast are few and far between, but it is always nice to have.

A short or long block V6 can be had for little money.

Ian.

[ianupton]

Rod - what drive ratio do you have?

Ian.

[Rocket]

1.97:1

[Rocket]

Ian, I may have the prop size wrong, they could be F9, I will check when I get home.

[MarkD]

dcasey:

I like Rocket have the 20 Baron and run a 350. It goes very well. My understanding is that a 454 will shoehorn in the Baron for sure, so it may fit the Bahia also. It is a bit heavy and the stern rides too low in the back. As many have said, if you want speed, the 350 is more than adequate.