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Bigger heavier!!!faster?

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  • Bigger heavier!!!faster?

    This past weekend I had a chance to ride in my buddies boat, it's a chaparral power play 23' BBC 454 23p prop. I have a four winns 211 liberator 23p prop it's doggy outta the hole but will get up and run pretty well. His boat is deaper higher sides longer and way heavier I pulled it with my truck and could definitely feel it. But his is way better outta the hole and a couple mph faster!!!What the hell. Wrong prop tired motor??

  • #2
    One boat is an apple and the other is an orange. If you had the exact same "Chaparral power play 23' BBC 454 23p prop" as you buddy, then you could compare performance.
    BOAT SPECS FORUM HELP STARCRAFT FORUM SHOP iboats
    Please, no PM's (Private Messages) regarding boat/engine problems.
    That is what the forums are for.
    Only forum/moderator issues will be answered in PM's.

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    • #3
      what is the deadrise between the two boats? what is the gear ratio of the outdrive? what brand of props? same ignition base timing? same air temperature in the bilge?

      the larger hull will have more planing area which helps initially
      1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - http://forums.iboats.com/forum/owner...988-rogue-2420

      Past Boats
      1970 Wooster Hellion - Merc 9.8
      2002 SeaRay 190BR - 5.0 - A1G2 - "Cheasheads in Paradise"
      1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

      What’s behind you doesn’t matter.Enzo Ferrari

      Comment


      • #4
        His dead rise is a a bit steeper, his prop is a Michigan mine is a ballistic not sure on gear ratio but he has an alpha 1 I have the baby king cobra, both with points and same ambient temps. But I had to use 4wd (worn tires) to pull his boat up the ramp and I've never had to come close to that pulling my boat. Same ramp same conditions. And yea I get it apples to oranges but my logic says my apple should roll faster then his oranges

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        • #5
          And it's not that it's a big competition.....ok maybe a lil but I jus can't wrap my head around it. I guess gear ratio could explain a lot.

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          • #6
            if he has an alpha, it has a 1.32:1 gear ratio behind the BBC
            1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - http://forums.iboats.com/forum/owner...988-rogue-2420

            Past Boats
            1970 Wooster Hellion - Merc 9.8
            2002 SeaRay 190BR - 5.0 - A1G2 - "Cheasheads in Paradise"
            1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

            What’s behind you doesn’t matter.Enzo Ferrari

            Comment


            • #7
              And the baby king cobra is a 1.5:1. But I'm not sure how to quantify that

              Comment


              • #8
                Originally posted by 211libwtfo View Post
                And the baby king cobra is a 1.5:1. But I'm not sure how to quantify that
                disconnect coil, put motor in gear, crank motor over 15 turns, prop should turn 10 times
                1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - http://forums.iboats.com/forum/owner...988-rogue-2420

                Past Boats
                1970 Wooster Hellion - Merc 9.8
                2002 SeaRay 190BR - 5.0 - A1G2 - "Cheasheads in Paradise"
                1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

                What’s behind you doesn’t matter.Enzo Ferrari

                Comment


                • #9
                  I found an old post from rick and it says 1.41:1. On the 7.5l baby kc sooo that would tell me again that my prop is turning faster than his which my boat should be faster than the power play???

                  Comment


                  • #10
                    The 1.32:1 alpha still spins the prop fadter than your 1.41 or 1.5 cobra drive
                    1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - http://forums.iboats.com/forum/owner...988-rogue-2420

                    Past Boats
                    1970 Wooster Hellion - Merc 9.8
                    2002 SeaRay 190BR - 5.0 - A1G2 - "Cheasheads in Paradise"
                    1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

                    What’s behind you doesn’t matter.Enzo Ferrari

                    Comment


                    • #11
                      Welp I'm gonna chalk it up to gear ratio then. Thanks Scotty. I'm gonna kick around freshin this bbf up over the winter. Rings gaskets cam heads?

                      Comment


                      • #12
                        Originally posted by 211libwtfo View Post
                        Welp I'm gonna chalk it up to gear ratio then. Thanks Scotty. I'm gonna kick around freshin this bbf up over the winter. Rings gaskets cam heads?
                        If I remember correctly, the MAX recommended RPM range for an OMC 460 King Cobra is 4200-4400 RPM.......

                        If your engine is turning 4400 (or close to it with the 23p prop) at wide open throttle (WOT) there's nothing wrong with it. You can improve the holeshot a little bit by going to a 19 or 20 pitch prop but to maintain the top speed, you'll have to exceed the recommended max RPM

                        It doesn't matter what you do to that 460, you're not going to significantly improve the holeshot.

                        My brother bought my FW 460-211 brand new in 1987. It was always a "Dog" outta the hole....but 60+ on the top end........

                        About 5 years later after the block getting cracked from freeze damage, he had the engine rebuilt by a 460 race guy in Redding Ca that builds performance 460's for Jetboats and he added Capts Call switchable exhaust, a different cam and some other trick "stuff".

                        He even went to 19p (repitched to 20 cupped stainless) 3-blade prop and it made it a little better but he had to run it at 5000 to get the same speed (about 60-62mph or so)

                        The boat picked up a few MPH but didn't come out of the hole much quicker. It was so slow on holeshot that his competition skiing wife didn't even want to ski behind it so he bought an 18 or 20ft Ski Nautique (350 MPI Mercruiser Marine) inboard ski boat (They REALLY holeshot quick!)

                        I bought the Liberator from him about 5 years later. The dismal hole shot was even worse because the camshaft had a few flat lobes and the engine would only turn about 4000 RPM at WOT.(the flat cam was probably due to him running it at 5000 all those years !!!)

                        I pulled the engine to rebuild it and when I found that I not only couldn't buy a coupler, but manifolds weren't available either except for new-old stock for a ridiculously high price (if you could even find them.)

                        That's when I decided to switch to a 300+ hp Volvo or Mercruiser + single prop drive. (didn't think I would want a dual, contra-rotating drive because they reportedly slow you down)

                        The 454+ Bravo III presented itself on Craigslist for a really good price and I bought it not knowing if it would also be a dog either in holeshot or top speed. All the info I read indicated that I would lose 3-5 MPH at the top end (which I could live with I guess)

                        As it turns out, when I took it down to California and ran side by side with my Brothers Nautique, the difference was nothing short of amazing!!

                        He could only beat me out of the hole by about 1 boat length and then, once up on plane, (which is nearly instantaneous) I ROCKETED right by him
                        (ski boats are not known for being all that fast in the WOT top end)

                        This was with a nearly 5000lb boat against a MUCH smaller lighter 18-20ft ski boat .....but both with similar prop HP (approx 300hp)

                        If you want that boat to come out of the hole better, get a 454/496 + a Bravo III or Volvo Duo-Prop drive.

                        It's just NOT going to happen with that King Kobra even with another 50hp (you'll just get more cavitation on holeshot) And it's simply not worth spending a LOT of money to rebuild the engine.

                        Cheers,


                        Rick


                        1987 FourWinns 211 Liberator, Originally an OMC 460 King Cobra.
                        Re-powered in 2006 with a 1997 Mercruiser 7.4L Bravo III

                        Comment


                        • #13
                          Well not what I wanted to hear but it had to be said and I appreciate it. I won't be able to afford that for awhile. Thanks rick!!! But on the other hand I'm really really considering an 89 searay weekender 30'. New port engine new gas tanks new Jenny heat/AC windlass full camper top 8k.?.?

                          Comment


                          • #14
                            Originally posted by 211libwtfo View Post
                            Well not what I wanted to hear but it had to be said and I appreciate it. I won't be able to afford that for awhile. Thanks rick!!! But on the other hand I'm really really considering an 89 searay weekender 30'. New port engine new gas tanks new Jenny heat/AC windlass full camper top 8k.?.?
                            Yeah, I want something bigger too......I have been kicking around getting a 10-12 year old Formula 330ss for quite some time! I love the Lib and the way it runs but I just want something bigger.
                            1987 FourWinns 211 Liberator, Originally an OMC 460 King Cobra.
                            Re-powered in 2006 with a 1997 Mercruiser 7.4L Bravo III

                            Comment


                            • #15
                              Sign up today
                              If you go to lake of the ozarks Craig's list site under boats, that's where I go for those kinda boats and dreaming I don't think you'll be disappointed.
                              Last edited by GA_Boater; October 3rd, 2017, 04:06 PM. Reason: Please!

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