How fast should I be? Am I missing something .
#1
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So I have a 31 awesome cat. Has gen 6 454’s procharged. The blocks are basically stock with stainless marine exhaust and 5 pounds of boost at WOT. Bravo out drives 1.35 ratio with 30 pitch props. I’ve trimmed anyway imaginable. I can only get the boat to run 4800 Rpms at 80 mph and that’s all with a half tank and one extra person l. It’s starts to pack air and I’ll I want is the extra speed to drive through it. 1. Should I be faster than 80 2. Should I lower my pitch or 3. Am I just flat out missing something. Any helps is appreciated.
#3
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That has to be the starting point to the conversation...
454 truck block came as a 230 hp - convert to marine + 5 lbs of boots would only give roughly 308hp
385hp 454 mag with 5lb of boost would potentially produce just over 500hp - a LOT of mph difference in the HP spread potential.
***Short answer/quick/definite answer is throw on a set of 28's and see where that run get you
454 truck block came as a 230 hp - convert to marine + 5 lbs of boots would only give roughly 308hp
385hp 454 mag with 5lb of boost would potentially produce just over 500hp - a LOT of mph difference in the HP spread potential.
***Short answer/quick/definite answer is throw on a set of 28's and see where that run get you
#5
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Thank you all for the responses. The set up has always been the same as for as I know and the motors are 454’ mags. I’ve usually do all my motors and maintenance but drive ratios and prop pitches are a little out of my league so far. Reason I’m on here asking the experts. Lowering the props was going yo be my first start but I really wanted options instead of guessing.
#9
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From: Baton Rouge, La
I don't know anything about the model boat you have, but when I had blown 509's I was running a 1.5 ratio bravo 32p bravo's. I would think the 1.35 ratio bravo's with the 30p props is a lot of gear for 500Hp 454's. I am not an expert just my opinion. Like others have said try some lower pitch props and I bet you see better performance.






