Flat tappet question

Discussion in 'PSI Superchargers Tech Questions' started by John byob, Sep 5, 2022.

  1. John byob

    John byob Member

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    Hi wanted to know how much less power it would make than a roller cam set up in a blown hemi. Looking to make 1600 hp but trying t get away frm taking off the valve covers every round to adjust them? Thx PS old fuel billet heads.
     
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  2. John byob

    John byob Member

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  3. John byob

    John byob Member

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    Basically same engine combo
     
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  4. vwsamba

    vwsamba Member

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    If you don't want to check valves between rounds a Hemi is not for you. Get an LS with hydraulics.
     
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  5. John byob

    John byob Member

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    Yes I hear ya but too late. Thx
     
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  6. MaggiFinn

    MaggiFinn New Member

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    The cam and lifters are actually the least of my worries after every pass, when the covers come off.
    They probably would be if they where flat tappets though.
     
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  7. Templar Motorsports

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    You should always be checking for broken springs. If you are running older hemi heads, you need to be checking to make sure you haven't burnt or blued any pushrod cups/ball adjusters too.
     
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  8. John byob

    John byob Member

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    Yes t that but I am by myself at the track and trying t cut down on re setting the rockers, I don’t mind removing the covers. It’s just being myself to reset the lash will be hard.
     
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  9. John byob

    John byob Member

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    If going t a flat tappet helps me achieve that I rather loose some hp than do more valve adjusting
     
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  10. Bob69

    Bob69 Member

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    you are less likley to need to adjust between rounds with roller lifters than a flat tappet. Go a little easier on the lift with a roller and you wont need checking.
     
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  11. John byob

    John byob Member

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    Ohh good to know, but what lift might that be? All the ones I have r 7:50 lift and std rocker ratio with wide pad non roller rockers.
     
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  12. John byob

    John byob Member

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    PS how come those BBC blown Chebbys can do it and they have 7:50 roller cams?
     
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  13. Bob69

    Bob69 Member

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    Probably due to having more lube coming up through the pushrods.
    I have found up to .750 cam on the street engines dont need constant checking (if using a rocker shaft system)
    If a old hemi without a roller tip that would indicate to me that things are wearing not falling out of adjustment. Improve the oiling to the top end and things should at least hold for a meeting. (Indy style external lube line to the rocker shafts)
     
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  14. John byob

    John byob Member

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    Thx anyone out there have a pic on the how to to get that done?
     
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  15. Bob69

    Bob69 Member

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    Sorry I dont have any at the moment. Im tuning a car in a month or so that I did the modification on so will grab some photos then.
     
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  16. John byob

    John byob Member

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    Awesome bob thx brother
     
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