Let's talk oil pumps and harmonics
So, I'm getting ready to buy an E46 330Ci (big step up from an auto 325i, not sure how it'll compare to my rev happy AP1 S2000) and started reading about common mods and problems. Much to my dismay I find that extended RPM use above 6K can lead to backed off oil pump nuts, gear shearing, and engine destroying goodness. This is no bueno my friends. But why I ask? The general consensus seems to be crankshaft harmonics which made me dig a little deeper...
Lets look at some other inline 6's aside from the M54B30:
Toyota 2JZ-GTE: totally square motor 86mm bore x 86mm stroke. Nice beefy internals and can take 7.5K all day (the HEAD internals being the limiting factor).
BMW S54B32:Undersquare (.96) at 87mm bore x 91mm stroke. 8K redline.
Now the M54B30: Only slightly more undersquare than the B32 (.94) at 84mm bore x 89.6mm stroke. Likes to massage itself apart above 6k...
So what gives? What are the physical similarities and differences between the B30 and B32? Bore spacing, deck height (rod angles)?
Are the factory oil pumps/dampers interchangable?
Does either motor have a girdle?
Hell, what about crankshaft ventilation: does the M3 have more/beefier provisions?
No matter how you slice it; the $2k oil pump offered or the $200 kit are just band aids (or a cast) for an underlying problem...