I think my 2nd turbo is not spooling correctly. I have no check engine. Does this mean I have to get new turbos? I get boost up until about 3500 to 4500 and then it shuts down. Or am I completely stupid and that's normal?

 

You most likely have a control issue related t the vacuum hoses or solenoids. Bring it by a reputable shop as it can be big job to diagnose.