Announcement

Collapse
No announcement yet.

M10b18 cylinder wall cleareance

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    M10b18 cylinder wall cleareance

    Hi.
    Does anybody know what is the 'thickness' between the cylinder walls?

    For the M10b18 from the e30 318i
    And for the M10 with 1,6 L from the E21 (M41 i think was the name)

    ------------



    And while i'm at it, what about the M30b25?

    This is my research so far:
    M88/3, S38b35, S38b36, - 6,6 mm ( E28 M5/E24 M635Csi/M6 , E34 M5 )
    M90 ( the first generation M30 engines which was the M88 block but with a regular SOHC M30 head) - so the same 6,6 mm

    S38b38 - 5,4 mm ( E34 M5 )
    S50b32 - 4 mm ( E36 M3 3,2 )
    S62b50 - 4 mm ( E39 M5, E52 Z8 )
    S54b32 - 3,5 mm ( E46 M3 )

    ------------------
    Now about the M30s
    All these asumming that the blocks are the same M90 vs M30 from what i found the differences are in some extra strenght points for the M90 and different cooling channels.
    But do they apply to the rest of the sizes?
    Are all M30 blocks the same from 2,5 L all the way to 3,5?

    M90 - 3,5 - 3,453 cc - 93.4 mm bore x 84 mm stroke - 6,6 mm clearence
    M30 - 3,5 - 3,430 cc - 92 mm x 86 mm (total difference of 1,4 mm ...so 6,6 + 1,4 = 8 mm ?

    I base my calculations on this:
    s38b38 (94,6 mm bore with 5,4 mm ) vs
    s38b36 (93,4 mm bore with 6,6 mm)
    And the bore differences 94,6 minus 93,4 = 1,2 mm
    Witch is = with the difference between the wall clearences 6,6 - 5,4 = 1,2 mm
    Makes any sence so far?

    The other size:
    3,3 - 3,210 cc - 89 mm x 86 mm ( 4,4 mm + 6,6 = 11 mm ? )
    3,0 - 2,986 cc - 89 mm x 80 mm (same)
    2,8 - 2,788 cc - 86 mm x 80 mm (7,4 + 6,6 = 14 mm ? )
    2,5 - 2,478 cc - ?? mm x ?? mm

    -----

    So did i do the calculations right? and/or did anybody measure it ?

    ---
    I measure it on my M50b20 block and it was ~ 10 mm so pretty thick.
    And i'm trying to find out how was it on the M30s and M10s.

    #2
    Well, seems to be my night for math.

    M10 bore spacing is 100mm. M10 piston size is 90mm (ok, 89.1, no overbore). So you get 10.9 mm between bores on the m10.

    M30's were the same bore over here, so again, 11 mm.

    M20, M/S50/52/54 have a different bore spacing, so you'd need to know that
    to figure out cylinder wall minimum thickness. (I don't know it off the top of my head..)

    hth, as far as it goes.

    t
    now, sometimes I just mess with people. It's more entertaining that way. george graves

    Comment


      #3
      Perfect.
      Thank you.

      Comment

      Working...
      X