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Thread: K+N air filters

  1. #1
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    K+N air filters

    Would a set of K=N filters make a performance increase on a pair of 300 mpis, Is it worth the expense over the factory Merc arrestors ,

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    several threads on this

    There are a couple of discussions on this subject in the Donzi registry threads if you look - basically there is no performance advantage to K&N but Mercury Racing uses this type of filter on their performance motors -
    Dr. d

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    I don't think the K&N is USCG rated.... maybe now they are, but a couple years back they were not
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    Not really.

    I have been fooling around with step and non-step 26-28ZX's for quite some time. There is only one way to get a bump in speed that you will really notice and that is to add some bigger hp.

    You can do some things to improve seat of the pants power (ie exhaust) and they are not bad mods but if you want to mash down the sticks and see 5mph or more it is gonna take some dough.

    Be careful of the trap "this mod will add 10 hp." Folks tend to do that and think that they will see something. They do the air filters (maybe 10 advertised), exhaust (20 advertised) and ECU reprogram (another 20) and think that they will get 50 hp. So that is 350hp and almost the power of a scorp? The problem is that it does not really work that way.

    Your best mod you can do without adding boost or going into the engines is exhaust. That will compliment mods you do later. You may see a mph or two. It will also sound a little better and have better throttle response.
    2001 35 Fountain Lightning w500 EFI's
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    1974 Chris Craft Roamer with 1271 TI's

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    Quote Originally Posted by BUIZILLA View Post
    I don't think the K&N is USCG rated.... maybe now they are, but a couple years back they were not
    I think you are correct on that, not USCG Rated. But they are legal if you have the breather tubes from valve covers to the filter assembly.The base of mine states K&N Marine S.A.E. J1928. Do they increase performance, probably not, unless you put a new/clean filter after removing a old/dirty one. Then you might could tell a difference, only because of a clean filter! They DO LOOK GOOD...the "Bling Factor" you know.of course, I have old school carb setup.
    "YIPPY-KAI-YAY"
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    So my best bet is to either get a faster boat or a pair of pro-chargers, has anyone done a set of blowers on twin mpis, to get an evaluation of the cost verses satisfaction and is this a reliable set-up. I dont want to be under the hatch all the time just to go out for a day. Maybe the 70-73 is what I should be happy with but everything I own has a turbo on it. lol

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    Quote Originally Posted by Need for Speed 2 View Post
    So my best bet is to either get a faster boat or a pair of pro-chargers, has anyone done a set of blowers on twin mpis, to get an evaluation of the cost verses satisfaction and is this a reliable set-up. I dont want to be under the hatch all the time just to go out for a day. Maybe the 70-73 is what I should be happy with but everything I own has a turbo on it. lol
    70-73 mph is a nice speed.

    If you really want more, you may as well go big. Mark Boos did a set on a 28ZX and ran well into the 90's, maybe a little more.

    It is all in the setup. A number of us run boosted engines successfully.
    2001 35 Fountain Lightning w500 EFI's
    1973 X-18 - Merc 383 Magnum
    1974 Chris Craft Roamer with 1271 TI's

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    My Formula had K&N and I detested them.

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    You will see no difference.
    Cheers,
    Pismo
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    75.5mph best @ 4800rpm GPS (Speedo said 82)

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    you wont see any noticeable power or speed increase with the K&N's.. However if the bilge is dirty or throws a lot of dust or belt dust they will help keep the air going into the engine cleaner than the metal flame arrestors... Jamie / Lakeside

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    Thanks for info guys. I was speaking with Mark Boos, looks like a pair of whipples and some compression reduction , ecm reflash. Seems like a very nice and knowledgable fellow. They had this boat last year set-up and it ran low 90s. I would be thrilled with mid 80s. Thanks again for pointing me into Marks direction. Kevin

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