What's interesting is that HP Autowerks also saw a 15ish who gain on their 1M when they switched out the midpipes and Borla catback muffler. I wonder if the N54 midpipes are as restrictive as everyone thinks.
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2018 BMW M3 ZCP
1999 BMW Z3 M Coupe Turbo
2017 Ram Rebel
2015 Porsche Cayman S
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