Supercharged E39 M5 touring squeal

[@DougBe38]

I was trying to message you on bf.com but, for whatever reason, I can't. Are you still making, able to make or willing to make a trim ring for an nbt setup for an e38?

[@jamesbrinkley5925]

Is that the blow off valve making that noise? Did you ever determine the source of the squeal?

[@bmwe39m5]

Mine makes the same noise..

[@XL5Master]

What navigation unit is that??

[@740iz06]

NBT, where did you get it all ?