valve spring install height - 1.785 instead of 1.8 spec ok for comp beehives?

Discussion in 'Engine Topic' started by fstarocka, Jan 18, 2021.

  1. fstarocka

    fstarocka Member

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    Have a set of comp beehives and an aftermarket alu head with a comp xr288 cam -


    Coil bind/etc issues aside i purely wish to know if such a small amount will be ok? Dont really want to cut the pockets if I can help it..

    I need spring locators cos the beehive is 7/8 (0.875) ID and the guide is about 9/16 (0.560) -

    The current install height is 1.845, if I use a spring locator (-0.060) ill end up around 1.785, 15 thou shy -

    will this be ok? Street 383 im building.. and im checking everything with digital calipers as the valve height micrometer is off low thousandsths..
     
  2. fstarocka

    fstarocka Member

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    Ok - to quote lunati:

    " An installed height of +/- 0.020" is acceptable." https://www.lunatipower.com/valve-spring-tech

    Now - My guide OD measure 0.560, the beehive ID measures 0.875 - what retainer specs can I use? whats the tolerance with clearances, 20 thou as well? going to try get a match for the sizes but might be out slightly (too big of course).. the OD f the beehive lower is 1.33 or thereabouts-
     
  3. fstarocka

    fstarocka Member

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    ok - so seems for my alu heads these fit the bill -

    COMP Cams 4705-16

    Outside Diameter of Outer Spring (in):1.300 in. (fits the beehive spring)
    Inside Diameter of Inner Spring (in):0.570 in. (fits bronze valve guide with 5 thou to spare)
    Locator Thickness (in):0.050 in. - PERFECT! will leave me at 1.795 install height :)
     
    Last edited: Jan 19, 2021
  4. 1320feet

    1320feet Veteran Member

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    What lift is your cam and what is coil bind ht of spring?
     
  5. fstarocka

    fstarocka Member

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    cam lift is 520/540- coil bind on beehives is 0.8 or 9 iirc.. plenty - plus I have 50 over retainers.. ill be doing pv checks this week but managed to find "ok" locators, really wished i could get some 0.045's but couldnt find any.. strange that comp doesnt have a 0.040/0.045 offering.. so ill be 15 thou under at 1.785 for 1.8 spec on the beehives..
     
  6. 1320feet

    1320feet Veteran Member

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    I should have asked for valve lift. If your valve lift is .540, then 1.785 - .540 = 1.245. Lots of room.
     

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