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  1. #1

    Join Date
    Jan 2007
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    Time to brag: new top speed

    Previous average was 61; today I averaged 62mph with a top speed of 62.4. I can attribute a bit to slightly cooler water, another bit to "true-ing" my the intake grate & rideplate, and a little more to modifying my new intake grate.

    God help you if you ever have to remove the intake grate on a Sportster/Speedster 150. They are simply not meant to come off. It's hard to believe they designed it that way. Reaching under the engine to work with the main bolt was a bloody hell.

    The intake grate has a very blunt edge; when I got the boat, I grinded that edge down to a sharp point, but I did it in a way that would direct more water into the pump. At that time, I naively thought the more water that could be loaded in the pump the better. That grate eventually ripped off (my fault, missing a bolt), so on my new intake grate, I grinded the bottom this time to direct that water under the boat instead of into the pump, because I have since learned that the pump needs loaded with less water at high speeds. I repainted it with gloss black, then installed it with all the bolt holes filled and sanded.

    I've gained a little over 5mph with my mods from the same time last year when I was completely stock.
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  2. #2
    18* here right now and I'm reading about your mods! All I can Say is good for you, sucks to be me!

  3. #3
    Doo It Till It Hurts! holdnon72's Avatar
    Join Date
    Feb 2007
    Location
    South Jersey
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    Glad to hear about your new found power!

    Just think Mandoo January is allmost over and when january ends we will have just 8 more weeks of the really cold stuff so hopefuly it will go quick!!!

  4. #4

    Where did you get the prop.

    How much accel did you notice?

  5. #5

    Join Date
    Jan 2007
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    Quote Originally Posted by MarsT
    How much accel did you notice?
    It's all about the acceleration. A 5mph gain on the top just doesn't justly describe the power I have now. I'm dealing with a lot of hull drag on top that's limits how much I'm going to get there, but the acceleration isn't even comparable to how it was stock. To give you an idea, I can out accelerate and outrun my neighbor on his '04 GTX-SC ski. Another one of my toys is a 400hp Jaguar, 0-60 in 5 seconds, and I feel no difference in acceleration between the two.

    I wish ya'll a short winter and that boating season comes soon... unfortunately for me, when it's boating season for you, our lakes become bathwater and I'm going to lose a mph or two.

  6. #6
    VX1-----Where did you get the new intake grate? Mine broke off as well and I need a new one.

    I still have to drill out the main mounting bolt (broke off), but once done I need to install a new grate.

  7. #7

    Join Date
    Jan 2007
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    Quote Originally Posted by mgurgone
    VX1-----Where did you get the new intake grate? Mine broke off as well and I need a new one.

    I still have to drill out the main mounting bolt (broke off), but once done I need to install a new grate.
    Of course I wanted to order it here, but they only list ski parts, so I went through Babbitt's Online. Nice site, with a parts schematic of the entire boat with prices for almost every part. I was pleasently surprised that the grate was only $46.73.

    The grate doesn't come with the bolts, though. I ordered the large bolt up front ($1.95) because I had no idea what size it was. They also sell the smaller bolts for $1.95 a peice, but those are just standard M6 (1.00*16) bolts that your can get at Lowe's for less than a dollar for a bag of 4 of them. They don't sell the washers, but you can can get those at the hardware store too.

    After what I went through, I feel sorry for you that you've got to do the same job. You'll need a mirror and flashlight to see under the engine. You'll need to remove your SC intake hose to get to it. You'll find that the bolt under the engine has hard silicone all over it. You'll need a knife of some sort to break all that off (and some silicone to redo the job afterwards). If I remember correctly, the bolt is 14mm. After the bolt is off, you can get under the boat with your drill and stripped-screw kit and get the bolt out of there. I stuck a piece of metal in the oven, heated it up, and placed it on the bolt, but I didn't have to heat it much at all. You find that it turns in the opposite way you might think, and that's probably why it broke in the first place. When you put the new bolt in, be sure to cover it with a gasket maker like the "Right Stuff". It's a mess and you will end you getting that all over your hands when putting the bolt back on under the engine. Be sure you have a large washer under that bolt too. Blue-loctite the other bolts and fill in the bolt holes with the gasket maker. Sand then down smooth the next day.

  8. #8
    VX1: Wow not looking forward to doing that job!!! Makes me want to just leave it off....

    Yea I broke the bolt turning it the wrong way when I got a rope stuck in there. Did you drill out the broken bolt....or were you able to get it out once you un did everything from inside/under the engine?

  9. #9

    Join Date
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    I drilled a small hole about half an inch deep through the center of the bolt with a titanium bit, then went under the engine to remove the nut... used a broken-bolt extractor kit (Wal-mart, I believe), in which the extractor bit is driven up that hole in the bolt, then I was easily able to unscrew it (just make sure you're going the right way).

  10. #10
    Jeepster's Avatar
    Join Date
    Jul 2007
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    Quebec, Canada
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    Hey VX1...my grocery list is about complete, all i still need is a water strainer...few drinks...and a beautiful day wrenching all this together...just can't wait to ride it with the goodies...
    I didn't purchased the intercooler from Jerry, but thought it was a good place to put one of his sticker there...! In a Jetboat there is a bit more room than in a PWC, so there is a slight chance i might still see that decal once installed....who knows...?

    Last edited by Jeepster; 01-28-2008 at 08:51 PM.

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