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  1. #1
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    How far can promax heads be cut

    Another thread got me to thinking but I've been wondering this a while now.

    A factory promax head has a pretty big chamber 38cc??

    i have 2 sets cut down to 34cc and want a set down to 26. Would I be better off getting a factory set of 26cc heads off a 260 etc or just cut these down.

    I habe a set of 28cc one piece 2.4 heads that still have good meat to them but don't know what they started life out as.

    Seems like even at 34cc the water jacket is starting to get pretty shallow on my pm heads.

    Thoughts??

  2. #2
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    60 views and nobody knows how far they have cut stock promax heads down before they get into issues with the head being too thin and the waterjacket being too shallow??

  3. #3
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    At some point don't u have to machine out the water jacket?
    81' HYDROSTREAM VECTOR / slightly Modified 200
    before and after:http://www.screamandfly.com/showthre...inished!/page3

  4. #4
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    Quote Originally Posted by texasvector View Post
    At some point don't u have to machine out the water jacket?
    I know at some point you need to weld up the chamber and reshape it, don't know what that point is.

    I know to get down to 17cc you do but don't know the point you should or shouldn't take down a set of stock chamber heads.

    I was just curious I need another set of 26cc 2.5 heads. Don't know what the others started out as.

    I have a set of 34cc cut promax heads that has some peppering from a lean piston failure and was going to cut them but don't know if it's a good idea to cut these down that far.

    Not 100% ready to do them yet but was curious. I can cut them to 32cc no problem for sure, just wondering if I should look for a stock set of 26 instead.

    I'll ask my head cutter he'll know I was just curious and didn't want to bother him since I was t ready to do it this week.

    Just trying to plan a few things on a new build.

  5. #5
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    Update: too much work to get down to 26cc and have them cool right etc etc.

    better off finding a factory set of 26 for what I'm doing

  6. Likes FORBESAUTO, texasvector liked this post

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