Even a 3" exhaust will certainly have more restriction that this design. But that’s really not important. The point was not to find a cheap option, the point was to build a system that had the very best of both Worlds.
With the dump closed, the car idles as quitely as a stock Honda Accord. Cruising the car is almost inaudible, perfect for having a conversation or listening to tunes. Open, the car transforms into a race car, loud, responsive and obnoxious.
The value in this system is not the cost or that there are cheaper alternatives. The fact that I can have two different cars and switch between then in lest than two seconds from the push of a button was the experiment…and the dyno is proof positive that it has worked.