I have been running without the friction modifier for a while,but on the street it was just not fun.Drove like a spool at speed and through the corners it would just push the front tires.I added a bottle of GM modifier and fixed that,and all the low speed popping and snapping that really didnot bother me.
One slick must be spinning just a little and were not seeing it , on YouTub Pinecone 917 video my car makes the same sound