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| do any of u guys do any boating or work on boats http://www.woodsbuggy.com/phpBB3/viewtopic.php?f=16&t=10427 |
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| Author: | wildwillie [ Wed Oct 06, 2010 11:38 pm ] |
| Post subject: | do any of u guys do any boating or work on boats |
iv got a 226 baja with a big block in it and im tryin to get more to end out of it. |
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| Author: | ole2timer [ Thu Oct 07, 2010 1:19 am ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
i think you can change the prop and do some good willie |
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| Author: | Rick [ Thu Oct 07, 2010 2:21 pm ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
WILDMAN WHAT DO YOU HAVE? MERCRUISER OR OMC ALPHI BROVO ONE OR THREE OUTDRIVE? ARE YOU RUNNING AT THE MANUFACURES MAX RECOMENDED RPM? FOR MAX SPEED YOU WANT TO BE AT THE TOP OF THE RPM RANGE AS YOU KNOW  FOR ALL THE YEARS IVE BOATED IVE TRIED EVERY THING FROM DIFFENT IGNITION SYSTEMS TO MANIFOLS, EVEN FULL OUT EXHAUST. YOUR BEST BET COMES IN THE FORM OF THE RIGHT PROP AND LESS WIGHT. YOU HAVE TO MAKE BIG HP TO GAIN ANY KIND OF SPEED AT ALL.
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| Author: | Maddog [ Thu Oct 07, 2010 5:20 pm ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
Willie, I have a baja 21 ft express cruiser that had a 330 hp 454. I had the big valves put in the heads with porting plus installed summit racing largest hydraulic cam. Also added a 9 inch sternjack to outdrive to space it further back. Then added an 850 holley double pumper with eldebrock intake. With the custom 27 pitch pitch prop she will do 78 mph. Needless to say, I spent somewhere around $3000, for 9 mph. At full speed there is only 1 to 1 1/2 feet of boat left in the water. Back to you going faster, try bigger carb and intake first. Oh! and it does love fuel, if you open her up. |
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| Author: | rockrockets1 [ Fri Oct 08, 2010 8:08 pm ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
That was my problem ...Open her up you could watch the fuel gauge drop  Nothing sucks gas like a Ford 460  Then wide ass open thinking you doing good look up some feller eases by you in a big ass Bass boat with a outboard 
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| Author: | wildwillie [ Fri Oct 08, 2010 10:02 pm ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
the wether has beed nice so iv got a chance to play with it some.what iv got so far is a new crate 454 and a 23pitch prop trimed out i can run along at about 67-68 mph on gps.but idid notic my prop is bent a bit so id like to buy a new one and iv been told to run a 21pitch and it will help my top end.but i dont know if it will hurt the boat plaining out. and props ant cheep! |
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| Author: | Rick [ Sat Oct 09, 2010 8:10 am ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
a 21 pitch is going to pull alot harder out of the hole, plus will turn more rpms! i would look for something in a 23 pitch 4 blade prop. |
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| Author: | chris38375 [ Sat Oct 09, 2010 10:14 am ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
wildwillie wrote: the wether has beed nice so iv got a chance to play with it some.what iv got so far is a new crate 454 and a 23pitch prop trimed out i can run along at about 67-68 mph on gps.but idid notic my prop is bent a bit so id like to buy a new one and iv been told to run a 21pitch and it will help my top end.but i dont know if it will hurt the boat plaining out. and props ant cheep! a 21 pitch will slow u down,if u dont have any trouble now with it planing out you can go bigger,i had a 26 pitch on a 115 mercury and it would out run 150 mercury black max motors |
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| Author: | ky-bc [ Sat Oct 09, 2010 12:43 pm ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
Will, what lake you been going to, Laurel? spent all summer on it and going tomorrow....you gonna be there? I have a 20' Larson 350 Chevy, merc alpha one. 19 and a 22 pitch props. The 19 jumps out of the hole big time, 60 mph tops with the 22..... There's a prop shop here in Somerset that will fix your prop...... |
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| Author: | Maddog [ Mon Oct 11, 2010 1:50 pm ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
You can probably pull a 25 pitch, and can always have it pitched to 27. That is the prop I run pitched to 27, wide open 5500 to 5700 rpm. I don't recommend any 4 blade prop for speed. Which crate 454 did you buy? A good prop shop, can be very helpful,mine let me try different pitches. |
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| Author: | Minnesota_Duane [ Wed Oct 13, 2010 12:44 am ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
rockrockets1 wrote: That was my problem ...Open her up you could watch the fuel gauge drop Nothing sucks gas like a Ford 460 Then wide ass open thinking you doing good look up some feller eases by you in a big ass Bass boat with a outboard Mines thirsty too. 
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| Author: | Txfly [ Wed Oct 20, 2010 11:51 pm ] |
| Post subject: | Re: do any of u guys do any boating or work on boats |
...Need more info on the boat, that thing should be running at least ninety. Bigger pitch, more speed, smaller pitch, better holeshot. Pitch is an imaginary thing. In theory, pitch is how many inches the boat moves in one revolution of the prop. In reality there are a shiton of variables. So in theory, if you have a 23 pitch prop, the boat will move 23 inches per revolution, or at 5000 rpm, 9583 feet ...make sense?...Reality then comes into play, weight of the load, coefficient drag, hull design, prop design...pulls those numbers way, way down. Blades are heavy, like un-sprung weight on a car (steel wheels vs aluminum), the most efficient blade is a single, but counter-weight might as well be another blade (two blade). Blades like clean water, the more blades, the less clean water at speed....and yes aluminum props are much faster. More blades, better holeshot (usually)...ski botes run six to jump the skier on plane quicker, more surface area, top end doesn't matter. Wheel (prop) diameter also plays a big part in that, fewer blades, bigger diameter, less weight, same surface area, higher RPM's...complicated. If you were running an outboard, I would tell you to add a jackplate and trim tabs, but since you are inboard ( or sterndrive) I would tell you to add trim tabs...or learn to use them if you already have them. Trim tabs affect the lift of the stern as opposed to "trim and tilt" which affects the bow lift (there is a difference). LENCO elec tabs rock, no hydro lines to screw w/. And they're fast. Don't go out and put monster tabs on, because you will sink the boat and kill yourself. I'm assuming the boat is in the 20' class, I wouldn't go bigger than 9"x12" on it. What will happen is you will lift the stern of the hull off of the water creating less drag, then you trim the bow. If your RPM's are in a happy place right now w/ the prop you are running, then you will need to re-prop w/ a bigger pitch. Props are very complicated, the rake in a prop creates bow lift, and the pitch determines speed (more or less), if you "cup" a prop, it will hold more water, but you will lose top end from the drag. A REAL good prop guy is a blessing, find a prop you're somewhat happy w/, tell him what it's doing and not doing at different RPM's, and let him put the hammer to it. It'll make you happy. My boat is a purpose built for fly fishing in very shallow water, it is a 17' carbon fiber hull, that weights 250# and is powered by a 60 horse, it tops out at 37 mph, but get's up in what it will float in ( about 7 inches loaded) and will do that in half a boat length because that's what I need it to do, and it will run in wet grass w/ the plate up. I built a prop "vise" and hammer my own props til it feels right. Hell, I knew guys that kept hammers and mapp gas on their boat and did it on the water! I used to run an 18' bass boat w/ a 150 (back in the late 80's), I could leave most 20's w/ 200's standing still at 65 mph. w/ a top end of 78mph GPS'd...My prop guy listened to me and did what I wanted, and I had a jackplate...and it was a badass hull design. A little speed tip: don't wax the bottom of the boat, scuff the "pad" (where the boat runs on plane) crossways to get more air under it, less friction (old racer tip). Hydrodynamics are a mind boggling thing...the electrolysis that happen when a prop is spinning in itself is just freaky. I know a guy running a 350 Merc OB that will top out at 98mph on a fishing boat...he says it does use more fuel, but since he get's there in half the time it balances out. (And I've seen him shear 1/2" stainless bolts on his jackplate)...the "Scalded Ape" is the name of the boat, and yes, it has the grafix to match the name. It's a 22' tunnel, it scares me just to look at it. I'll do what I can to help, I'm not much on inboards, but I kinda know how most of it all works... I hope that made sense, there's a lot to take in (kinda like woods buggies to me). Good Luck, Tx |
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