Quote:
|
Originally Posted by swamp2
Quote:
Originally Posted by BMRLVR
The fact that they look in much better shape than bearings from stock engines should tell you that the OEM rods inability to stay round on the big end bore is a contributing factor to the bearing wear.
|
If you are implying that BMWs S65 rods are also of an insufficiently stiff design than I say your rampant, unabashed speculation continues to amaze me... I don't think anyone would deny the causal relationship between insufficient rod bearing bore stiffness and premature bearing wear. However, if you think BMW does not know the exact peak load, stress and resulting deformation of the rods in this engine under all peak load conditions from a detailed finite element and kinematics simulation then quite frankly you're mad. Of course
Is their design sufficient for 300k mi of longevity at 15k mi oil changes?
Do aftermarket rods offer an improved big bore (or overall) stiffness?
and other such related questions are interesting but I won't speculate on them. |
You act like cost is no object to BMW. Everything they put in a mass produced engine is not going to be the best of the best!
Of course a carillo rod is stiffer. That is carillo's business, they make rods that are stronger than what engines are specced with from OEM!
Did BMW not have a recall where E46 rod bolts were replaced with stronger ones? I am sure they did there testing in the S54 too...... But they ended up beefing up those rod bolts three years into production!