They're in, and they sound sweet. As far as sound goes, it's exactly what I wanted. With the top up, there's a low rumble, more like a hum. I have no scientific fugures for restriction reduction, but a number of things should be obvious. The old pipe was 1 5/8", the new 2 1/4". The old pipe made a 90* turn in front of the gas tank, where the muffler sat close to the rubber fuel line; the old muffler had the outlet next to the inlet, indicating a 180* flow reversal. The new pipe goes to a low restriction muffler in front of the rear axle, and then a pipe goes over the axle to exit at the stock location. All in all, there is much less pipe length, and one 180* and two 90* bends less. It is not intrusive on the road, and it sounds like a late model GT at idle and low speed.
