Big-Block/MGX Fuel Mileage Question

[BobA]

Installed Minstral exhaust and already had the free flow air cleaner in there for 5 or 6 k miles. After the exhaust install the fuel mileage seemingly has dropped noticeably and exhaust smells rich at idle. I typically only ride in open spaces (No FL) so that hasn't changed. And yes I definitely ran it harder the usual the first few hundred miles to see how I felt about the exhaust note. I always ride in the 80-90+ mph range so that hasn't changed either. Just curious if anyone else noticed a difference?

And the exhaust sounds very good! Don't see the need for the Minstral tuner mod but maybe that's the problem?

[Bulldog9]

I averaged 35MPG on my bike, and mileage also went down when I put the Agostini's, subconsciously wanting to HEAR it    A few tanks, using the bike to commute to work 15 miles each way, I got less than 20MPG..... Total gas hog.