Cant get RPM out of a 454, 330hp
#32
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From: Millstadt, IL
#34
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From: Millstadt, IL
From the one's I have seen it is very small. I have a Bravo looking at it from behind, it is stamped on the upper on the left side on the label. I am not as familiar with the Alpha's, but it may be in the same location.
#36
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From: Millstadt, IL
#37
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I have the same problem. Got a '91 454 running a 19 prop on a 24' bowrider but with a bravo drive. But just the same, I can only get 3800 rpm and topping out at about 35-40 mph. Have a really horrible hole shot. Take forever to plane out, unless the boat is passenger free and then its just okay, probably where it should be if I where loaded down. Boat just lugs out of the hole. Feels like no low in power. Have you figured out anything?
#38
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From: Millstadt, IL
After looking at my Bravo drive a little closer I do not see the ratio stamped on the drive. It used to be marked on the label but I removed it earlier in the year. I can still see the serial number as it was stamped. But the drive ratio must have just been printed or marked on the label. So that may be why you cannot find it. Seing that it is a Alpha and not a Bravo, the advise given before about puting it in gear and rotating the engine may work.
#39
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From: Bettendorf, Iowa
I have the same problem. Got a '91 454 running a 19 prop on a 24' bowrider but with a bravo drive. But just the same, I can only get 3800 rpm and topping out at about 35-40 mph. Have a really horrible hole shot. Take forever to plane out, unless the boat is passenger free and then its just okay, probably where it should be if I where loaded down. Boat just lugs out of the hole. Feels like no low in power. Have you figured out anything?
I got all the way down to an outboard vensura 19p 4 blade prop. i think it had a 13.5 diameter. compared to the props i am running now.... itys little. the holeshot was crap and i got 49 mpg out of it at the end of that season. pretty sad.... i got 74 once this year with a Bob Madera engine!
#40
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From: Bradenton Florida
you sound like you have my old problem. I have a gen 5 engine (1992 build) it had a flat tappet cam. They took alot of the zinc and phosphorous materials out of standard oils. those additives made it easier on the cam and flat tappet assys. i kept running less and less pitch. the boat kept going slower and slower. tore the engine down for a build up and found (count them!) 5! 5 flat lobes. i wanted to scream! when i got it to the machinist we both sat there and guess horsepower with a cam like that... we both know it couldnt be over 200. you need to retro-fit over to a haydraulic roller setup. Bob Madera can help you there. im sure your engine needs freshening up. and from here on out run race oil.
I got all the way down to an outboard vensura 19p 4 blade prop. i think it had a 13.5 diameter. compared to the props i am running now.... itys little. the holeshot was crap and i got 49 mpg out of it at the end of that season. pretty sad.... i got 74 once this year with a Bob Madera engine!
I got all the way down to an outboard vensura 19p 4 blade prop. i think it had a 13.5 diameter. compared to the props i am running now.... itys little. the holeshot was crap and i got 49 mpg out of it at the end of that season. pretty sad.... i got 74 once this year with a Bob Madera engine!


