Question repower volvo penta from 5.0 with duo prop what type HP can this handle

Hello I have a 2006 chaparral 235 with 5.0 gxi-f motor hook to transom Sx-M with drive DP-sm 1.95 M22 wondering what HP This will handle. Looking at building a 400hp stroker. Will drive and transom handle it?

IMO, it is unlikely that a true Marine Built 6.3L SBC (aka 383 cu in) will produce an honest 400 hp. If it were to, it may not be suited for Marine cruiser use.
BTW, you want torque not necessarily horse power..... and the best way to gain 6.3L torque will be in doing a Q/E build.

You may want to peek at these threads:

Twin-350-s-to-twin-383-s

Begin reading at post #7 here.


As for the added torque that it may produce, it would be best if you went to the 1.78:1 lower gear unit and re-propped.
The 1.78:1 gear set is a bit more stout.


The transom shield will hold up to the power/torque.


Also, your hull is almost 11 years old, so I would look closely at the "structual transom".
The added torque will be placed against the transom, so it must be in great condition.





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