Paughco exhaust.....Yay or nay? Pros and cons, if any, I would greatly appreciate. Of course, I also wondered how they would sound on my evo softail. I had never heard of them until the other day...price caught my eye.

 

I have no complaints and never heard anyone else complain.

 

Paughco makes good stuff. Just avoid drag pipes. Their solid pipe with the mufflers are nice

 

Why avoid the drag pipes? There are several versons of them, one of which I was considering.

 

If you run drag pipes, be sure to use some type of baffles in them.

 

They're bl**dy awful - whatever brand! You will probably suffer a 'hole' in the torque curve, right where most of us like to ride. Not a good choice IMHO.

 

The best pipe I've seen so far for low end torque is Supertrapps.......

 

Is it the diameter (1 3/4") that makes them drag pipes? I really like the look (smaller diameter) for an older evo.

 

No, it's the fact that they don't have any baffling between the start and end of the pipe. Just a tube for exhaust to flow thru, nothing more. Great for high RPM work but ***** in the midrange.

 

The pipes we know as 'drag' pipes are derived for drag racing! They are also known as 'tuned length' pipes, meaning they are cut to an optimum length to give best power and torque in the selected rev range.

When the exhaust valve opens it sends a shock wave down the pipe, which as it leaves the end of the pipe sends a shock wave back towards the valve. Engine tuners use this to their advantage, by using cams which hold both the exhaust and inlet valves open, allowing some of the fresh charge to escape down the exhaust pipe. The inlet valve is timed to close before the exhaust valve, so that the rebounding shock wave catches the escaping fresh charge and stuffs it back into the cylinder, effectively over-filling the combustion chamber.

This feature only functions well over a narrow rev range and stumbles outside that, hence poor performance in lower rev ranges. It isn't really suitable for a street bike and adding baffles of any sort is a bit like invoking voodoo.....