Originally Posted by A418t81
I worked for APR, there were hardly any reports of blown turbos. I have also had 3 tuned 1.8Ts in the family, all with 50K+ miles of chipped "abuse." They were all fine. I have 3-4 friends with chipped 1.8Ts with mileage in the 70k+ range, they are all fine. There is not that much mention of turbos failing on vortex. There will be turbos to fail, but some will fail regardless of boost. Your guy replacing two in a year or two is doing something wrong, or maybe you are during installation. Are you replacing the feed line every time?
Regardless, APR has become a premier engineering house, and works directly with VAG/VW racing. They see fit to run those turbos that far off the map, and call them reliable. If there were a significant issue with this, it wouldn't have been done. In fact, there is not a SINGLE 1.8T tuner that lives anywhere close within the confines of the compressor map.
Finally, cost is a consideration, but with BMW stuffing the N54 in every car they make, and with aftermarket turbo solutions looming the horizon, I don't feel it will be that much of an outlay in the future to pick up some stock replacements. Hell, people already occasionally find them in perfect condition for $200 on ebay.
One other point I wanted to make, but forgot about, is that I feel the hotside is more of a bottleneck than the cold side. I think that as compressor flow nears peak mapped flow, the hotside is already a bit closer to nearing peak flow, and is negatively impacting the VE of the system. This obviously would dec the CFM the compressor would need to flow at higher PRs in relation to the math above as preturbine pressures (even post turbine pressures in cars with stock DPs) increase, especially in the 6k+ region.
And youre spot on, to a point.
You read on these forums, and its warranty this and warranty that.
You make it sound like no one gives a shit about the warranty. If thats the case, hell yeah crank the boost up. That has always been the underlying tone of my argument.
If you dont give a flying shit about your warranty, thats the way to go.
Here is a scenario to ponder...
Say Joe Schmoe has a 335i. He has been running with a box since his car was new. At 30k, his car starts to shown signs of turbo failure. So instead of risk going to BMW to have them replaced, he picks up some stock ones for $200 and has someone install them. A year later, something catastrophic goes wrong. He takes off the mods and goes to BMW. In their inspection, they can see signs the turbos have been tampered with (could be something as simple as wrenching marks on one bolt). Whole powertrain warranty is toast.
You shouldnt be running shit on the ragged edge and expect BMW to pick up the tab. And as long as this keeps happening, expect the anti tune measures in the software to increase along with the scrutiny of the techs when ANY service is being done.