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Factory Installed Valve Stem Height

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  • Engine: Factory Installed Valve Stem Height

    I have a question about valve stem height. Here's what I have, a 259 out of a '58 Transtar. The heads are in a shop being redone and they've asked me for the factory installed valve stem height, spring seat to the tip of the valve. I have searched the shop manual and found nothing. Does anyone know the specs? I would greatly appreciate it. Thank You - Jim

  • #2
    Doggone it! I just KNOW I read that Spec. Somewhere, I just checked for you in one the Best Shop Manuals, the 1956 Version that has '57 and '58 Supplements that I didn't look for, and Nowhere in the 259/289 Engine Section Under Valves or in the Engine Specs. page did I find the Installed Valve Height.

    I know from memory that I did set them with Shims, at very close to + or - 2 Inches, because after Head Porting and valve grinding my Seats were deeper weakening the Springs.
    The Std. 259/289 Valve Spring Tension is 105 to 115 Lb. at 1 43/64 Inches.

    Maybe where it is more important to keep the tension at 155 Lbs. with stronger Springs on higher revving Avantis, they will show the Installed Height.
    StudeRich
    Second Generation Stude Driver,
    Proud '54 Starliner Owner

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    • #3
      Just measured one to be sure , 2.030 with a clean valve and seat. this is from the spring seat to the underside of the retainer. Luck Doofus

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      • #4
        Originally posted by StudeRich View Post
        Doggone it! I just KNOW I read that Spec. Somewhere, I just checked for you in one the Best Shop Manuals, the 1956 Version that has '57 and '58 Supplements that I didn't look for, and Nowhere in the 259/289 Engine Section Under Valves or in the Engine Specs. page did I find the Installed Valve Height.

        I know from memory that I did set them with Shims, at very close to + or - 2 Inches, because after Head Porting and valve grinding my Seats were deeper weakening the Springs.
        The Std. 259/289 Valve Spring Tension is 105 to 115 Lb. at 1 43/64 Inches.

        Maybe where it is more important to keep the tension at 155 Lbs. with stronger Springs on higher revving Avantis, they will show the Installed Height.
        Seriously ?
        +/-2 inches..? That's a 4" possible difference..! Sorry, but that I believe is...impossible.
        The "springs are NOT weakened by setting the seat deeper. Just the effect of changing the installed height to something longer than the recommended 2.03" changes the springs rate, it does NOT weaken the spring !

        While I don't have the actual number, I had a tool made up years ago to check the "valve" installed height.

        The 2.03" mentioned is the "spring" installed height...NOT the valve tip height. This includes the retainer.
        You could do some reversing measuring of the spring location of the retainer height.
        Measure the distance from the spring/retainer (while mounted to the valve with a pair of locks) interface, to the valve tip.
        Add that to the 2.03" dimension, that will be very close to the valve tip installed height.

        Mike
        Last edited by Mike Van Veghten; 10-16-2020, 06:36 AM.

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        • #5
          The only written spec I've seen is "Installed height - 2.032"

          jack vines
          PackardV8

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          • #6
            Originally posted by Mike Van Veghten View Post
            +/-2 inches..? That's a 4" possible difference..! Sorry, but that I believe is...impossible.
            Mike, I believe what Rich meant was slightly less or slightly more than 2".
            Paul
            Winston-Salem, NC
            Visit The Studebaker Skytop Registry website at: www.studebakerskytop.com

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            • #7
              Exactly! Geeeze can't a Guy forget to Dot an "I" here?
              Of course a tad more or less than 2 Inches is VERY close, and what I meant.

              And of course the word SHOULD have been LESSENS the Spring tension, not weakens, but everyone but One, probably knew that.
              The Springs require Shimming to make up for the Valve Seat recession in order to maintain the specified spring tension.
              StudeRich
              Second Generation Stude Driver,
              Proud '54 Starliner Owner

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              • #8
                And i measured 2.275 spring pad to valve tip. a tricky operation after coffee and before insulin! sounds like the head shop may have installed hard seats and are checking their work. Luck Doofus

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                • #9
                  As you can see from the measurements recorded here this is a nominal measurement. It's going to differ by several thousands of an inch depending on how much material has been ground from valves and sets. I would not bet that brand new engines from the factory all measured the same.
                  The machine shop probably asked for that figure because it is very important on engines with hydraulic lifters and non-adjustable rocker arms or other limited range of adjustment.

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