Props for a B28 with Cummins 4BT's?

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Face
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Props for a B28 with Cummins 4BT's?

Post by Face »

Any idea what props might be appropriate, or at least a start, for a B28 with twin Cummins 4BT's?
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In Memory of Vicroy
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Post by In Memory of Vicroy »

what gear ratio?

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Face
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Post by Face »

ZF 1.53 : 1
Eddy G
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Post by Eddy G »

What RPM do they turn? For reference, my Yanmar 240's with ZF 1.53 ratios are rated at 3300 rpm and I am starting out with 18 x 19 Nibrals and a #3 cup. I based my desicion on several other B28's out there with the same engine / drive system. Won't know any performance numbers until next week.
Eddy G.
Face
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Post by Face »

I'm not sure yet. I think they turn 2850 rpms.
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In Memory of Vicroy
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Post by In Memory of Vicroy »

If they are 250 hp 4BTAs they are rated at 3000 and should be propped to turn just over that, say 3050-3100 at full load WOT.

Eddy - have you got the Yan 240s in the Gotta Go yet? We gotta race up and down the Tickfaw sometime. Now that AJ is in her Howdy Boat config. she's fast.......

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Eddy G
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Post by Eddy G »

Vic, we are just about finished with the repower. Everything is in and hooked up. I have the yard doing a barrier coat / bottom paint job and the last coats will go on this afternoon and tomorrow. My shafts should be ready by mid week sooooo, if the monsoon they call for at the end on this week doesn't mess us up, we should do a seatrial on Saturday. I may leave the boat at the old camp for a week or so before I run it back to Madisonville. Maybe we can race to Middendorf's and loser buys the thin fried catfish. By the way, I need a CX Red can fix. Can I pick some up at your office one day this week? Thanks,
Eddy G.
Face
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Post by Face »

They are actually 150h.p. 4BT's. I just found a good prop calculator though. That should give me a good start.
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In Memory of Vicroy
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Post by In Memory of Vicroy »

Eddy - sounds like you are almost done. Sure thing, how much CX you need? If your old camp is not open I have tons of room at my dock behind AJ.

Give me a call at the office 927 9908 - I'll trhow some CX in the truck tonite.

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Eddy G
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Post by Eddy G »

Vic: I picked up the CX yesterday, thank you very much. We most likely will be visiting around the Tickfaw New Years weekend and if so, we will definitely come by to see you guys. Thanks for the invite. Happy Holidays to you, Mrs. Elaine and all you guys on the site.
Eddy G.
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In Memory of Vicroy
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Post by In Memory of Vicroy »

Good deal, look forward to seeing ya'll.

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