Band saw sound from left side of engine above 75mph
Before I get to catching up I just remembered I need some help. Time wise I had no choice but to hit the super slab home and kept a pace of 70 to 75mph indicated most of the way. After about 120miles I was getting antsy and just wanted to be home so I thought I would see how fast my baby could really get up to but as I was getting over 80 I noticed a metal grinding sound, like a soft band saw hitting metal, coming from my engine. I leaned in and listened as I speed up and slowed down finding it coming from the left side and starting about 80mph or 5500rpm and stopping as soon as I slipped under the 80 mark. Oh so close to home I didn't take time to see if 5500rpm in 4th or 3rd would produce the sound or not. Power wise I felt no difference and I am sure I could have made 100mph if I didn't notice the sound.
Is this normal at those speeds (my first time getting her that fast)? Could I have done something wrong when doing my Doo?