Same principle as the last one you asked about, only square. Dude, I'm not busting on ya, but do you know the principle of a tuned header/pipe? And why just about every pipe has the same basic layout? It has to do with the shockwave of the exhaust and how it is utilized to increase power. You can't just slap on a contraption of tubing and say it increases power and looks awesome. If you want to know the theory of the tuned exhaust, I'll write it for ya, but trust me on this, those pipe dream exhaust systems do not follow tuning theory. They may be loud and look cool and keep your truck from getting oily, but they will not make as much power as a good tuned header and pipe. You'd end up having to put a bigger engine in it to make the same power as the one you have with the stock pipe.
Here's a quote from that website that I find confusing and down right misleading:
We do not currently use fuel tank return line pressure fittings for several reasons:
1. They add extra cost to you.
2. They add extra unwanted weight.
3. All you need to do is stick your silicone return line into the predrilled hole.
4. Our testing has proven that they are not required.
First, how much is a brass fuel line pressure fitting? Not much. And if the "pipe" is aluminum, the fitting will self tap the threads.
Second, give me a break, a pressure fitting ads almost no weight.
Third, Sure, that oily fuel tubing is gonna stay put while you're bashing. I've seen it a hundred times at the track where someone is running their pressure line like that and boom, it falls out. Then the engine runs way lean and dies.
Lastly, test all you want, but I still don't believe that they are not required.
If you want to test these systems and post the results, by all means feel free. But what you'd save on not buying one of those pipes, you could have some other parts that would increase either power or handling.
I don't own a Maxx, but I do know engines.
