I need a header back exhaust system. I am looking at part number Part Number: 520-16521. However it states it will not work with automatic transmissions. Do you know why it will not work? My cross bar has a hole on each side to accommodate duel exhausts. So Questions, with some slight modifications can I make this exhaust system work? If this will not work, what part number would you suggest? I am currently running side pipes and they bottom out constantly.

ac = No

drivewheel = 2WD

engine = 350

fuel = carb

make = Chevy

model = corvette

pwrbrk = Yes

pwrstr = Yes

trans = th400

year = 1975

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