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Old 09-22-2018 | 10:59 AM
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Posted in the prop section as well..

So factory labbed 28 Bravos I get the rpms Im after but not the mph. Factory labbed 30 Bravo is faster but not getting the rpm I need for peak HP. Like 400 tpms from where need to be.. Ideas? Which ones should I have dialed in for my boat.
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Old 09-22-2018 | 11:41 AM
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Have the 28’s cupped for more bite, might lower rpm a little but not nearly as much as the 30’s.
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Old 09-23-2018 | 08:16 AM
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Im leaning toward working the 30s more being they are faster than the 28s even thought the rpms are lower than I need. If I can get more rpms out of the 30s I should be good. Just dont think working the 28s will give me the speed . Already turning the 28s hard enough bit the mph isn't there.
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Old 09-23-2018 | 05:31 PM
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Should be able to thin and sharpen the 30s for more rpm but keep the same pitch. In theory may result in more rpm and more speed
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Old 09-23-2018 | 06:08 PM
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Kinda what I was thinking. That and cut the diffuser off
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Old 09-23-2018 | 11:57 PM
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I'd be careful about cutting off the diffuser ring. Not that much to be gained and could make planing much harder.
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Old 09-24-2018 | 01:07 PM
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Originally Posted by Griff
I'd be careful about cutting off the diffuser ring. Not that much to be gained and could make planing much harder.
Ive done it on a set of labbed 30s and it did pick up about 100 rpms. 1 to 1.5 mph and allowed then to blow out a little right where I needed it. They had no blow out before, just enough blow out now to take the stress off the drives. Cut 1/2 in off.
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