Originally Posted by M335i Oreo Package
So the reason they changed from forged to cast in the middle of production was to keep people from running insane boost, which they knew was possible with forged pistons. Now cast pistons are now put into all of the motors (1m 335is & 335i)so that if you run excessive amounts of boost your warranty will be voided.
Director of tune detection
Originally Posted by Questforpower
Aren't the pistons the most important lol? The rods look pretty damn beefy either way if u ask me and the crank is the last thing i'd be worried on an Inline 6 motor.
Not really If I had to choose between the two I would take a forged rod. Look at how and where the forged rod cracked. One thing that has to bee considered it tune. I have seen well tuned cast component cars run amazing amount of power. Conversely I have seen forged internals fail at relatively low boost. If the timing and fueling are not where they need to be that broken rod is not uncommon.