Repower Question

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J Graham
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Joined: Oct 7th, '07, 10:58

Repower Question

Post by J Graham »

Has anyone repowered with the Cummins QSB-350? If so were there any issues or problems. Is this too much for this hull? I've seen many with the reman 330's but not many reman 370. Boat is an express cruiser with gassers and is being completely redone. Are replacement windshields available?
Thanks,
Jim
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JP Dalik
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Post by JP Dalik »

cricket.......cricket.........
KR


JP
1977 RLDT "CHIMERA"
J Graham
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Joined: Oct 7th, '07, 10:58

Post by J Graham »

cricket ????????
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Carl
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Post by Carl »

Yeah its the silence before it all starts.

Again.


It's kind of an ongoing thing, some think the xtra HP is a good thing, others think its too much for the hull in it's stock condition, that is without changing shaft angles, prop pockets, weight distrubution etc.

Every so often the repower subject comes up and gets into how much HP is too much, how fast is too fast, and it all starts over...again.



A few searchs here will get you the answers.
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Tommy
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Post by Tommy »

Jim,

Capt. Patrick has stated that he believes 240 - 330 HP is the optimum range for the Bertram 31 hull. As stated above, when you go above 330 HP, issues with prop diameter, shaft angles, and prop pockets come into play, all of which can be problematic. I had the 315 HP in my old boat, and it would cruise at an honest 30 knots (honest meaning with full fuel, water, four guys and gear). However, in any sea other than slick calm, I could not comfortably run that fast; so the extra HP/speed was seldom used. I found 26 knots to be plenty fast on a pretty day; and besides, you don't want to get there too fast (the trip is half the fun). JP is having some good natured fun because we've seen the issue beat to death on this forum, and you can find plenty of posts about it (and I'm sure more will follow). Good luck with your project, which ever way you go.

Tommy
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Mikey
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Post by Mikey »

Jim,
Are you talking about glass or frames? The lower frame on my express was useless. I bought a later front and curved frame and had to modify the boat as they are different from early to late models. The upper I had some welding done to repair the fractures and then powder coated the whole bunch. Cabin sides are American Marine in Florida. Good folks who do good work. Let me know if I may be of assistance. HAve totally redone an express with Cummins.
Mikey
3/18/1963 - -31-327 factory hardtop express, the only one left.
The difference between genius and stupidity is that genius has its limits.
-Albert Einstein
J Graham
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Joined: Oct 7th, '07, 10:58

Post by J Graham »

Thanks for the feedback. It"s an old family boat that the son has come across and wants to rebuild. He brought it to the shop that did my 25 which has a single 330 Cummins so when the power question came up they got in touch with me. I have seen much talk about the repower options and recall most people feel the 330 is more than ample. He wants electronic so the QSB is the logical choice if he wants Cummins. Just wondering if anyone on the forum has done one. I love my 330 (except the noise) and will put another in my next 25 one which is just getting started. As far as the windshield, they will be able to repair and powdercoat the original. This is an old timer that hasn't seen water for a long time. It'll be completely stripped down to the old stringers. It's great to see them come back to life.
Thanks again.
JG
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Ironman
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Post by Ironman »

Theres a recent redo in Newport harbor.. He used the QSBs & seems happy good lookin boat. Looks like they simply added height to the boxes .
Ive got the 330s & dont see any need to go any bigger.. Got a tower & still have no problem getting 30knots.
Wayne
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