-zadirani to opravdu nevysvetluje...ph132008 píše:Nevím, jestli se N53 zadírá víc na klice, ale má jí litou. N54 má kovanou s větším zdvihem.
-vyhodnost milimetrovych rozdilnosti ve zdvihu nedokazu posoudit
-na to dalsi jsem si radeji vzal na pomoc cloveka z e90 post ktery o tom vi vic nez ja...
"ALL BMW engines (and engines in general) have forged rods. Every time I see somebody bragging about forged rods in their BMW engine it drives me crazy! The N54 rods are just made thicker and with larger rod bolts than the N52, they are made with the exact same process (powder forged, cracked cap). Even an M10 4 cylinder engine from the 1960s would have forged rods..
Pretty much all BMWs used cast pistons, but these are not low-quality castings - in a lot of ways, they are superior to aftermarket forged. Not worth worrying about. I doubt many production cars use forged pistons, and not just because of cost - they have different thermal expansion properties (due to the materials used) and usually require more cylinder wall clearance, bigger piston ring gaps, etc - so you get more blow by, piston slap when cold, etc. Not things you want in a road car that you're going to sell millions of.
The cranks are primarily where there are differences, with some being cast and some being forged. Honestly, I wouldn't worry about it at all - BMW cast cranks are extremely strong, it's just that the forged ones have a better strength/weight ratio. The only broken cranks I've ever heard of have pretty much been money shifted."