I know the slipons vs full exhaust debate has been beaten to death, but I haven't found any full systems that I like. I currently have the V&H Straight Shot slipons installed and wondered if replacing the pipes themselves even do anything performance wise.

 

i wouldn't waste the time on it

 

not as much as you would think, In fact a lot of these short 2-2 full system are down on hp/tq in the meat of the power when compared to a stock header with good flowing slip on.

 

My opinion is only go with new headers if you are trying to change the way the pipes run a long the bike. I have shotgun pipes with run between my leg and the bike rather than under my feet. It was a performance preference thing, lose some hp and torque, gain lean angle.

 

Go here:

http://www.1250kits.com/ttxlexhaust.shtml#rushslipons

Add those and some tuning...

 

What Brasher said.

If your bike is stock or Stage I, changing out the headers will make no improvement, and sometimes are detrimental to power. The one exception is if you go with a good 2-1 system.

If you're looking for more power, install some Thunder Torque Inserts in your SS slip-ons, you will notice a marked improvement in low and mid range power, and save a bundle at the same time.

 

I've been amazed at the improved performance and smoothness of the Supermeg on my Glide. When the time comes I will fit a similar system on my Sporty.

 

Not a flow dynamic expert , but noticed most . if not all aftermarket full exhaust systems do not incorporate the cross over feature like factor stock setup.
Believe the cross over feature either from the slip-on connection or near the cylinder heads with straight single horizontal tube or the new design just in front of the slip/on, serves to increase low end rpm torque and not high end rpm power.
Would prefer low end torque to high end HP.
Agree with DK that the 2 into 1 pipe setup is preferred on a stock or stage 1 setup , since it simulates the cross over feature.
If replacing my stock exhaust set up would go with the 2 into 1 pipe arrangement, but would probably have to install a fuel management system in 07 & up EFI fuel system to adjust the fuel to air ratio.

 

The cross-over pipe was introduced by BSA back in the '60s/'70s on their parallel twins and it is they who discovered that it improves low/mid range torque. Within a short time all the other manufacturers of twins adopted them, including H-D. That was an era during which exhaust design began to blossom and the tuned length systems which are widely used nowadays were found to give even better performance.

So a modern 2-into-1, especially with identical tuned-length pipes, will give better performance than the older style factory system with a balance pipe. The Buells are a case in point, as using identical length pipes enables the engine to be tuned to a much higher output than a stock Sportster. The recently introduced big-twin 2-1-2 systems are essentially a 2-into-1 with twin tail-pipes.

 

Just do whatever looks best and sounds the best to you. Its a harley, if ya wanted performance Ducati would of gladly taken your money.