High rpm's low speed

sin1000

Cadet
Joined
Aug 5, 2020
Messages
19
I am new this forums so PLEASE take it easy on me :) I bought a 2005 Chaparral 210SSI that had a Volvo Penta 5.0 GL-E with a SX-M 1.60 drive unit, the motor block cracked just replaced motor with a Volvo Penta 5.7 Votex same drive of course the prop that was on the boat which I put back on is a Merc BlackSilver (something like that) it is 14" x 19P four blade prop as I did my 1st run with new motor boat was at 4k rpms but going 30 mph so I did not want to go that high on the rpms so I brought back to the dock took prop off in search of a new one any ideas?
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
42,572
Howdy
4blade 19 is equal to a 3 blade 21

For now break in the motor slowly and once you get 10 hours on it, then take it up to WOT and let us know what the rpm is.

Also make sure your speed is GPS and your tach is accurate
 

sin1000

Cadet
Joined
Aug 5, 2020
Messages
19
I am trying to break it in slowly, but I really do not like the high rpms the engine is making at this point not sure to go up or down on prop pitch to get a better rpm range
 

sin1000

Cadet
Joined
Aug 5, 2020
Messages
19
I take that back went to website here is what they posted

This BRAND NEW 5.7L Vortec GOLD package is great for those that need a little more than just a base engine or long block, but still don't quite need a complete engine package. This 5.7L GOLD package is rated at 315 hp @ 5000 RPM at the crank and will fit, bolt in, and work in nearly all 5.0L & 5.7L marine applications from 1986-Current with no modifications. (Pre-1986 applications will need to update the flywheel and in certain applications, the engine coupler). If you have an existing MerCruiser, Alpha One, Volvo Penta, OMC, or any other outdrive or inboard transmission, NO modifications or gear ratio changes are required when installing this 5.7L Vortec engine package. 12-3/4" or 14" flywheel available. This 5.7L Gold Package comes with the following components:
 
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