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  1. #1
    Committee, Moderator Matt Cole's Avatar
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    Valve velocity

    Anyone know what target valve velocities would be inlet and exhaust? 70,80,90 m/s?

  2. #2
    Non-member Andrew Cooke's Avatar
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    Re: Valve velocity

    no idea what you're trying to do, but you could work out what they are from the cam profile and rpm

  3. #3
    Committee, Moderator Matt Cole's Avatar
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    Re: Valve velocity

    Ha thanks Andy. I'm thinking of a bit of DIY head work. I think you know the cams I'm going to use?

    As you know the megane head has a strange port shape due to the injector angle. Theres plenty of meat in the way and needs to be removed and matched to my manifold. From there I was thinking of saving myself a fortune and look at valve seat and port shaping etc.

    I then thought what the hell am I trying to achieve and, hence my question.

  4. #4
    Non-member Andrew Cooke's Avatar
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    Re: Valve velocity

    are you talking about port velocities, or valve velocities?

    DIY porting is more likely to make things worse than better, there is a reason why modern engines make so much power. Any improvements will be within 1/4" of the valve seats, and be detail stuff.

  5. #5
    Committee, Moderator Matt Cole's Avatar
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    Re: Valve velocity

    Quote Originally Posted by Andrew Cooke View Post
    are you talking about port velocities, or valve velocities?

    DIY porting is more likely to make things worse than better, there is a reason why modern engines make so much power. Any improvements will be within 1/4" of the valve seats, and be detail stuff.
    Ok. I guess a specialist may be the best option. I do think that the meg head could be vastly improved as it seems a fairly rough casting.

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