Hey guys, thanks for the post! I just got an email from Tyler asking to come here and answer questions on the kit, so I'll keep checking in and answer, if folks have more questions/comments.
To kick it off though, some background, I wanted to design a kit that would give me and others the option of a 600+whp daily driver with stock-like driveability and part quality/reliability (using quality parts - BW EFR turbo, cast manifold, SS downpipe, etc)... for less than $5k.
As for the comments above on N55's bending rods above 600hp, I would have to agree with what was already said here, in that tuning plays a laaarge part of how any of these games plays out. Manufacturers design parts to have certain design margin (component stresses during worst-case combustion events) in place to hit their reliability targets with a distribution across thousands of vehicles. I know this, as I've been an engineer on the oem side of things for nearly 20 years... When turning up the knob to 2x the stock vehicle hp, we are using some of that margin. Now, when tunes are not quite dialed, and misfires and pre-ignition happen, the stresses in the rods/piston/crank can double, relative to a normal combustion event, so now rather than 2x the stress, we are at 4x the stress of a stock setup. When that happens, I'm not surprised if any engine, be it N54, N55, a smallblock Chevy or Ford, etc would see something damaged in the rotating assembly.
I've been daily driving my test mule (2014 335i) for this kit for about a year without issues. I would be interested in seeing and hearing about these other N55's that have had issues though. Does anyone have any background on them so we can help the N55 community?