Can anyone ID these pistons?

Discussion in 'Street/strip 400/430/455' started by Bigpig455, Jan 13, 2020.

  1. Bigpig455

    Bigpig455 Fastest of the slow....

    455 standard bore built in the late 70’s, block is 73 but these look like a much smaller dish, marked in the face with “STD” and a Star with a O next to it..
     

    Attached Files:

  2. knucklebusted

    knucklebusted Well-Known Member

    Is the head off or are you using a bore scope device? If you could measure the depth of the dish in the piston, it would help as perspective can be difficult in 2D.

    With those caveats, those look like higher compression pistons. How far down in the hole are they at TDC?
     
  3. Bigpig455

    Bigpig455 Fastest of the slow....

    Hey! Pistons are .032 in the hole, dish is .242 deep..
     
  4. knucklebusted

    knucklebusted Well-Known Member

    Unfortunately, those are likely low compression pistons. I'd guess about 8:1 CR with everything else stock.

    http://www.buickperformanceclub.com/pistons.htm
     
  5. Bigpig455

    Bigpig455 Fastest of the slow....

    I'll CC them when I pop em out..
     
  6. Thumper (aka greatscat)

    Thumper (aka greatscat) Well-Known Member

    replacement piston with higher compression than 9 to 1.
     
  7. Bigpig455

    Bigpig455 Fastest of the slow....

    I did the math and the dish is somewhere in the neighborhood of 36 CC. Big, long full skirts on these too, hang out the bottom of the bores. I was told by the guy that built the engine they were part of a rebuild kit, maybe TRW?
     

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