What HP is required to spin an "A2"?

[Wet Dream]

An AA or A2 needs what kind of HP to move a boat and can it be made to move efficiently at 4800 rpm? If so, what kind of speed can expected on a 19' hull with a Berkeley?

[LakesOnly]

Just a guess:
Berkeley with an AA impeller @ 4800 r.p.m.; perhaps 425 HP. Should exceed 60 mph.
This is a very general answer based on your very general info.
LO

[Wet Dream]

I know its broad based. But since the Olds isn't a high rpm spinner, can I make the AA work efficiently for high speeds under 5000 rpm?

[Heatseeker]

I'm running a AA in a 18'er. At 4500 rpms I gps around 60-63 mph, depending on the number of passengers.

[LVjetboy]

I think Lakes posted a good power estimate. I think the AA will be more efficient than smaller sizes no matter the power. But, if you want top speed, you match impeller to your engine's power curve...not necessarily most efficient...but may give the most thrust. The stock Olds rpm limit may be a factor here.
How fast your 19' hull goes depends on how much drag...consider hull shape, weight and bottom straightness. Nobody can tell you that unless they know your hull. Or you go out and measure a drag reference point then figure.
jer

[OkieDave]

I have two boats with AA impellors. One is a 23' Vee-bottom Firehawk(Baja-22.6 splash). It has a stock BBC and log exhaust. It turns 4600 rpm and goes 60 mph. It is a large boat by jet boat standards. My current other boat is a light weight gull-wing 18' with a 557 c.i. BBF, it urns 5400 rpm and goes a little over 90mph.
The large impellor has always been my choice for economy.There's always room for nitrous without revving way on up the rpms. Been thinkin about tryin one of those American Turbine AAA impellors.

[manuel]

Here is a power curve chart for different impellors and what HP and RPM max. numbers
http://www.***boat.com/image_center/showphoto.php?photo=34191&password=&sort=7&thecat=500

[TIMINATOR]

Chart doesn't go high enough!!!! In my opinion the more H.P. you have in a LAKE BOAT,the happier you will be with a BIGGER impeller. I run an inducer and AA and the fuel consumption is lower than most slower stuff! :D TIMINATOR