I've never seen 1 1/2", but even if they do make them I'd go with 1 5/8". And, I agree with 93CobraR... I would go with the long tubes. They are a bit harder to install from what I hear, but everyone I know that has shorties is planning the switch to long tubes, and everyone I know with long tubes says that the extra effort to install them was worth it. Just a thought, and it will probably save you some money down the road. As for the rest of the exhaust you picked the exact same parts I did so I think you made a wise decision going with MAC.
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