It's definitely welded on and basically bulletproof. No added harshness, I was actually surprised. It made the car a new beast, i would do it again if I got another M3.
Current: 1969 Ford Mustang; 351w; Champion 4 row alu rad; Edelbrock Intake Manifold; Holley 600 CFM Carb; Cragar Wheels; 215/60-15 f, 255/60-15 r; Doug Tri-Y Headers; Dual Side Exit w/Xpipe; MSD 6AL; Electric Fuel Pump; U/D Pulley Set; Monte Carlo Bar.
:( E46 M3 SMG; Evolve-R Tune; much, much more... 2980 lbs.
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