Originally Posted by elp_jc
Thanks for the heads up. I just mentioned that as a sidenote because I read several times of people using the subframe as a LEVER (bolts have nothing to do with that indeed) to install springs, so maybe they were doing it wrong
. But the issue here is that most of the failures seem to originate from BAD INSTALLATIONS (like exhaust brackets removed by shops), and abuse, not by a defect.
Furthermore, seems like you're trying to make it a more serious issue than it actually is to sell your part. Unless you abuse the crap out of your car, such as hard launches causing wheel hop (something it was NOT designed to withstand), or a shop doesn't torque the bolts properly after being removed, car is perfectly fine. Just look at the few cases out of thousands and thousands of cars produced. Good day.
If I wanted to make money off the people on this forum for something like you are claiming, I would have released something that was a half way done job with no proof that it improves anything.
I have been building very high HP cars for a very long time now. Reinforcing the subframe is a common practice, ESPECIALLY on BMW's. This wouldn't be the first BMW, or M3 for that matter that has a subframe prone to damage from usage.
As of right now, I am testing my designs to see if it will even work or not. There are MANY cars out there with this catastrophic failure now.
Thank you for your input, however, even removing the exhaust brackets from the car and improperly torquing them wouldn't cause this failure. The failure is caused from the loosening of the main differential bolt, it then begins to shear itself until broken or in some cases, it doesn't shear, it simply falls out. What then happens is the differential is clocked to a degree that it damages the 2 front differential mounts and damages the subframe.