not sure what is going on

[chickmagnet]

Friend called and is having me post for him so sorry if this makes no sense. he says it sounds like the car has very agressive cams but they are stock cams. What could have caused this all of the sudden? he has mbc, custom exhaust, and 450s.

 

[fulanititoo8198]

More info would be helpful. More agressive cams as in the exhaust note or as your hearing the looping sound in the engine bay? I'd start with boost leak test also checking for an exhaust leak since you said they changed their exhaust.

 

[chickmagnet]

problem fixed. bad vacuum line.