Crower cam kit

Discussion in ''Da Nailhead' started by SubCool, Aug 15, 2020.

  1. SubCool

    SubCool SubCooled

    I recently came across a old unused Crower Cam kit for the nailhead. I need to get over and look at the cam card again but it was about .480 lift and came with special lightweight Crower lifters and inner valve springs, retainers and shims. What's funny is the lifters had the hole for pushrod oiling. The guy who had the stuff said it was very similar to a comp 265 grind. Why would they just include inner springs in this kit instead of a complete spring set up
     
  2. wkillgs

    wkillgs Gold Level Contributor

    Isky did that too.... just included the inner springs in their Nailhead kits.
    Inners alone can increase spring pressure, maybe they are easier to make or fit more than one application than the outers?
     
    SubCool likes this.
  3. SubCool

    SubCool SubCooled

    there must be a difference in the Crower inners and the factories that require a different retainer and that's why they include retainers as well. I'm going to get a picture of the cam card when I go back over to his house later this week.
     
  4. SubCool

    SubCool SubCooled

    Cam card DSCN0942.JPG
     
  5. wkillgs

    wkillgs Gold Level Contributor

    We need to know the tappet lift those open/close specs are taken at!
    Buick likes to spec their cams at 0.002" lift, the industry standard is 0.006" for 'advertised' duration, and 0.050" is the more common standard.
    A call to Crower would be in order.
    When I have more time, I'll take a look at the specs I have saved.
     
  6. gsgtx

    gsgtx Silver Level contributor

    don't think you can have 480 lift with only 264 advertise duration, that's about 210 duration @ 50 thousand with these old cams. can't be measured @ 6 thousand advertise with that high lift. cams that size most times would be about 450 lift.
     
  7. Babeola

    Babeola Well-Known Member

    Thats has a 110* lobe separation straight up ( in at 110* intake). It could be advertised duration depending on what it is, and where and how they have decided to measure that (solid lifter cam advertised durations are taken at .015" or more) . In any case, single pattern cams are more old tech and not the most efficient in these exhaust limited engines. A split pattern cam favoring the exhaust is a better ticket to power.

    Cheryl :)
     
  8. wkillgs

    wkillgs Gold Level Contributor

    Those valve events are similar to a stock cam at 0.006" lift. A little less duration than stock, so about 205 degrees duration at 0.050. A little more lift, and 110* lobe separation like the older 401 cams.
    The stock 66 401 cam I measured had the following at 0.006" lifter rise:
    Intake opens 19.5 *, closes at 72*..... duration = 271.5*
    Exhaust opens at 65*, closes at 21*..... duration = 266*
    Lobe separation = 114.5*
    Intake lift = 0.448"
    Exhaust lift = 0.425"

    If Crower isn't measuring the open/close points at 0.006", this comparison is useless!
     

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