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Camshaft regrinds / compression

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    Camshaft regrinds / compression

    Hey to all ,
    I just resently had my 2.5l head rebuilt and also had my camshaft grinded . (stock)
    I assembled the engine , everything was cool . but noticed that it didnt have the balls that it hould've had . My 87 325is bucket is faster .

    #1 cylinder before the rebuild had 155 psi .
    #1 cylinder after the rebuild has 120 psi

    A friend who is a machinist at Larrys Performance Shop in Montebello , Ca told me that Regrind cams will have lower compression than a Factory Cam .
    Is this True ???

    #2
    Regound cams have less valve lift.

    Less valve lift = less air can enter per intake stroke.

    Reground cams suck.

    Buy a real cam.
    Tenured Automotive Service Professional - Avid BMW Enthusiast

    Vapor Honing & E30 ABS Pump Refurbishment Service
    https://mtechniqueabs.com/

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      #3
      Less compression is pure BS. Some regrinds will have less lift but usually the grinders will add material before grinding to get the exact some profile as stock.

      A properly ground and heat treated cam is just as good as a stock billet.

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        #4
        Originally posted by Jordan
        Reground cams suck.

        Buy a real cam.
        All those old sayings; such as 'too good to be true' and 'you get what you pay for' and etc. apply in this situation.
        Adam Fogg- '88 M3

        Common sense- It's the new 'gifted'

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          #5
          Did the oil on your #1 cylinder dry up or get wiped down?

          I sold a 84xxx mile short block to some guy, the #6 & 1 pistons were down
          at bdc and the oil dried up in the 8 months it sat in my shop.
          The guy didnt bother throwing some oil on the cylinder walls befor puting it
          back together.

          He called me up saying he had low compress on 1 & 6 I told him to take the
          plugs out of those cylinders and put some oil in the holes to help the compression. It worked for cylinder 1 but it was too late for cylinder 6 the rings on the dry cylinder wall scratched the crap out of the cylinder.

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            #6
            cam has zero to do with compression. bad rebuild. poss. broke a ring reassembling it.

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              #7
              Originally posted by mikeedler
              cam has zero to do with compression...
              Cams have zero to do with STATIC compression, but they can affect the DYNAMIC compression of the engine.

              Back OT: Probably has to do with the rebuild, unless they ground too much off the cam.

              The standard compression test has more to do with the static compression ratio of the engine, which makes me believe something is wrong with the rebuild, not the regrind of the cam.
              San Diego BMW repair -> Jake @ www.littlecarshop.com Great guy :up:

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