VetteLT193

Anyone ever swap a Bravo 3 boat to Bravo 1's?

Formula 280 SS, twin 350 Mags. Drives stolen but assemblies are there. I can get a much better deal on Bravo 1's than Bravo III's...

I'm thinking a Bravo 1 with a good 4 blade prop would work? I'm concerned on the major difference in ratios between the two, among other things.

Griff

I would think a 280 with Bravo 1's would be fine.

38fountainecman

I switched out my bravo III to a bravo I on my Fountain 38 express cruiser and gained 5 mph on top end and did not lose any in the mid range and very, very little getting on plane. I was running bravo 1 four blade props. The boat was a little tougher docking, but nothing I coudln't handle.

VetteLT193

Holy crap, 5 MPH!

We have a deposit on a set of used Bravo 1's... 1.5's. now we need to figure out props.

According to the old top speed, 55-ish it needs a 17-19" set of props... is it worth trying a bigger set in hopes the bravo 1 efficiency is that much better?

jeffswav

Bravo 1's are way faster, I would definatly get the Bravo 1's.

38fountainecman

Vette: on my fountain, the current set-up is 1.88:1 reduction with 25" pitch set of bravo III XR props. The XR props have four blades on the forward prop and three blades on the trailing prop. My boat ran 60 mph at 5K. When a went to the bravo 1, I had a 1.5:1 drive with a four blade 26" bravo 1 prop. I had to overtrim the drive to get the rpm's to 5K and hense the top speed of 65. (speeds were on my gps speedo) I figured that I either need a 1.65:1 drive with the 26" bravo 1 or a 24" bravo I with the 1.5 drive. Based on what I have read in powerboat mag and on OSO, I would try spinning the largest pitch prop, the fewest revolutions). What was your old drive ratio? It may be trial and error, not quite sure.

LAKESIDE RESTORATIONS

The single prop drives have less drag & parasitic loss. The twin prop drives can give a better hole shot (as gears & shafts will allow), and they have a tendancy to track straighter in both forward & reverse. Jamie / Lakeside

VetteLT193

Thanks for the info. We don't know the old ratio, bought the boat as is without drives.

I have done a ton of research, Bravo III setup runs 55 top end. So I was shooting for that speed... but maybe a bit higher based on your experience?

We're trying to not spend a bunch of money on it, bravo III's are newer and less popular so they are more money in the used market.

ezstriper

you will be much better off performace wise with the B1's !!