1968 Cal 34 need prop and shaft

[Capt D Scott]

I have an atomic 4 gas motor. I need to get so advice on the prop pitch and size. Atomic recommends several. Any suggestions?

[alamoana]

Hi Scott, to get good advice more information is needed. LWL of the boat and weight, HP of engine, RPM max and reduction gearing. Regards

[Capt D Scott]

Forgot to mention it has a V-Drive
15000 Lbs
30' lwl
rpm max 3500
Reduction 2:1

thx

[Capt D Scott]

Have to see if V-drive also reduces the drive ratio

[rickmartyn]

SailboatData.com shows the following specs for Cal 34:

Waterline length = 26 ft.
Displacement = 9,500 lbs.

https://sailboatdata.com/sailboat/cal-34

[Davidhoy]

Originally Posted by Capt D Scott

I have an atomic 4 gas motor. I need to get so advice on the prop pitch and size. Atomic recommends several. Any suggestions?

Frank and Jimmies Prop Shop in Fort Lauderdale helped me with a new shaft, coupling, etc last year. Great guys, very helpful. I already had the prop, but I'm sure they could help you find the right size and pitch, given the engine HP, max RPM, transmission reduction ratio, and some info about the boat.

-David

[Capt D Scott]

Thanks everyone for the help!!!!

[JimsCAL]

The 2:1 reduction is a big deal because most of the A4s were direct drive (1:1) and thus used a small fine pitch and thus inefficient prop. You should thus ignore most of the prop recommendations you find online.

[Brigadoon]

On my Ranger 33, I replaced my bronze shaft which was badly eaten away probably due to stray current in the water.
I got a 316SS replacement and a new cutlass bearing from Deep Blue Yacht Supply and am happy with the result
http://www.deepblueyachtsupply.com/prop-shafts