What's the mileage on your 35i?

[X5goldie]

Are you still on the original turbo? Can these turbo engines hit 200K?

Trying to get some feedback if I should jump on one at 133k.

Thank you.

[andrewwynn]

Mine made it to 195 and self destructed fantastically!

My replacement motor has 120 and i don't expect any problem getting past 200. The original motor wasn't well maintained before i bought at 144 and i pushed it hard.

There is a flaw in the design that I'm working on fixing. The DME controlled oil pump runs 5-10% lower psi than it should so I've developed a method to boost that up with a dial. You can dial up from 0% to maybe 25% boost in oil psi.

There is a rash of spun bearings on the N55. Between me and one buddy we are the owners of four n55 paperweights.

One (mine) failure was at full throttle full boost and the autopsy suggests boost got into the crankcase and disrupted the oil flow to the rod bearings. At redline it took just seconds to fuse at least 2-3 bearing shells to the crank. It took a 24" pipe wrench and 10# sledge to free the rotating assembly.

Wife's blew the OFHG and blew oil out at high pressure. (whole side of engine soaked).

Not sure exactly how pull starvation happened except possibly lost over a quart of oil, pickup tube sucked air when she braked and minor starvation spun a bearing.

Inn either case having an extra 5-8# of oil pressure to start with would have more than likely saved the motors and minor repair (replace the CCV check valve that failed to put boost into my engine, replace her OFHG. Much much muuuuch easier than replacing two motors.

Until my motor self destructed it ran beautifully!

I wouldn't hesitate to own another n55 but that also includes that i will boost the oil pressure. I will be posting the how to when i install it ≈ end of February.

Learn how to prime the oil circuit and out of an abundance of caution i would prime even after an oil change. Mine seized 1-2 weeks after an oil change without prime of oil circuit.