Which Y-Pipe on lowered F-body???
If you dont know how to adjust it you can do heater hose mod.
my Flowtech ypipe tucked up really well. they put small indentations in the top of the pipe where the 3" pipe comes close to the frame, it allowed for 1/4-1/2" more clearance with very minimal affect on flow.
but the merge sucked...
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