3.73 for a full bolt on car// 3.55 for a power adder car. I'm using 3.55's, I feel like anything more aggressive will be useless with anything over 400wheel.
I can show two dynographs next to eachother of my OEM mani vs Long tube mani runs. Long tubes pick up 20-30lbs throughout the powerband. Huge throttle response gain and more mid range power.
Looks like you may be rubbing the filter on the subframe. Have you checked your motor mounts for excessive play ?? I cant tell by the pic but it looks like it rubbed through.... unless someone is poking pin holes in your filter :(
Has this only happened once or is this an intermittent problem you've been experiencing ? When Traction control activates it will slow the car down, was the ABS Pulsing at all ?