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  1. #1
    Robsauto2's Avatar
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    Whats best 4 EFI ski?

    I need to make a choice for my 07 boat, either I install the 3 degree keyway or R-D heads for compression.

    I would like to do both but am worried about deto because of the California piss they sell here called "gas" at the pumps.

    91 octane is the best we have here and sometimes I wonder if its even that. So what would you choose?

    Another idea, I had good luck with 1 layer of head gasket on my 2000 boat, has anyone tried that on the non-pv motor, and what was the compression before and after? Thanks guys


  2. #2
    WATER WOODY's Avatar
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    I gained about 7psi when i went to 1 layer.I had problems with that and others have too.Some guys are running with one gasket and are doing good.I dont recommend it but thats just my opinion. If you dont have the EFI controller,i would run the heads.That is a good start.I strongly suggest you reinforce the pump tunnel first.That would be my first investment.Ive heard both ways....EFI controller if you use a keyway and the total opposite.I can get away without the controller at my elevation with a keyway,sea level may be different.Someone will comment on this for you.Try and get rid of you stock intake grate and get the R&D.

  3. #3
    KamikazeGPR's Avatar
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    Brian(suckmywake) is running 1-layer gasket on his stock comp 05. I think he told me it's a 10-15psi increase over stock. He's been running the 1-layer for awhile now. Not sure what he's using for gas, I think i saw him fill up with 89 on the water at last forum ride.

  4. #4
    You might consider a set of my throttle bodies Rob. They wont change your octane requirements and will add a nice midrange hit with added top end also.
    Clik on my myspace link for pics and more info..
    My 06 went 73.4 on a 1200 grate with same mods as yours, minus efi controller, with the ported throttle bodies..
    Thanks, Ross

  5. #5
    Robsauto2's Avatar
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    Quote Originally Posted by WATER WOODY View Post
    I gained about 7psi when i went to 1 layer.I had problems with that and others have too.Some guys are running with one gasket and are doing good.I dont recommend it but thats just my opinion. If you dont have the EFI controller,i would run the heads.That is a good start.I strongly suggest you reinforce the pump tunnel first.That would be my first investment.Ive heard both ways....EFI controller if you use a keyway and the total opposite.I can get away without the controller at my elevation with a keyway,sea level may be different.Someone will comment on this for you.Try and get rid of you stock intake grate and get the R&D.
    Yeah I have the EFI controller and modded 800 grate on it, see my sig. I will do the tunnel reinforce soon.

    Maybe a combo of both, install the key and remove 1 layer of gasket.

  6. #6
    Robsauto2's Avatar
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    Quote Originally Posted by rossnemo View Post
    You might consider a set of my throttle bodies Rob. They wont change your octane requirements and will add a nice midrange hit with added top end also.
    Clik on my myspace link for pics and more info..
    My 06 went 73.4 on a 1200 grate with same mods as yours, minus efi controller, with the ported throttle bodies..
    Thanks, Ross

    Ross what was the air temp on that run?

  7. #7
    800AMSOIL4U's Avatar
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    WFO where are you?

  8. #8
    It was right at 80 degrees Rob... These EFI engines dont change that much with the weather like carb engines usually will.. I took mine out on a 85 degree day last fall on a saturday, then on sunday after a front went through and it went exactly the same speed, on a 20 degree temp drop. That was before i had an efi controller on it also. The richer you are, the more you will pick up when temps fall.. It would go consistent 72.4-72.8 at 7260rpms that way, no matter what the weather was. I did have my 85mm exit nozzle bored to 87mm though..

  9. #9
    Happily Self-Employed WFO's Avatar
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    Quote Originally Posted by Robsauto2 View Post
    Maybe a combo of both, install the key and remove 1 layer of gasket.
    I personally wouldnt be afraid to raise the compression a little and do the key... but I do like to push things a little.

    I am with Woody on the single layer thing... lost a piston due to water intrusion before. I do have a few boats down here with a single layer, but we pull the head(s) and replace the gasket often and inspect everything.

    If you are afraid of detonation, you could always do the heads and key, and go with a freeflow.

  10. #10
    Robsauto2's Avatar
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    Quote Originally Posted by rossnemo View Post
    It was right at 80 degrees Rob... These EFI engines dont change that much with the weather like carb engines usually will.. I took mine out on a 85 degree day last fall on a saturday, then on sunday after a front went through and it went exactly the same speed, on a 20 degree temp drop. That was before i had an efi controller on it also. The richer you are, the more you will pick up when temps fall.. It would go consistent 72.4-72.8 at 7260rpms that way, no matter what the weather was. I did have my 85mm exit nozzle bored to 87mm though..
    So what prop are you running to get those rpms? I have an 87MM exit nozzle laying around, maybe i'll throw it on for fun.

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