Ive got rinehart true duals on my relatively stock 07 roadking.I see most of the guys with built motors running the 2into1 pipes.Is there any benefit to run a 2into 1 pipe on an otherwise stock motor.I did notice less low-end torque when changeing from stock pipes to the duals,but they sound nice.i plan on doing the 103 kit and cam when $$ is available.Probably change out the exhaust at that time.Let me know what the deal is with the 2 into 1 pipes.Thanks

 

When I had my bike dyno tuned, I used a PC3, there was a 07 Ultra being done right before me. I have a 07 Road King.He had true duals and I went with the Rinehart 2 into 1. My bike put out 7-10 hp more than his across the rpm band. He had a SE AC and I went with Doherty's. Don't remember the torque difference but it was in line with the hp.

 

This should be interesting. I don't think this has been discussed before

 

About every month or so.............I just copy and paste my response...............LOL





Forestfarm........................use the search function for this forum, you'll find a lot of info discussing this exact comparison.

Steve

 

For pure performance the 2 in 1 pipes are absolutely the best gain, I ran a Vance Hines 2in1 pro pipe with a competition baffle on my last bike great performance and sound especially when you kick it down a gear! I really like the dual bagger look on the Ultra so I will stick with the Supertrapp SE slip ons, I like the performance of the cross over pipe, like they say true duals you loose bottom end torque except for maybe the Bassani head pipes with their power curve.

 

True duals will make less HP and torque than a two into one,on a stock motor.
I don't know if this holds true on all built motors,to many variables,but if you
build for low and midrange power,you'll probaly still find the 2-1 to work better.

 

in most cases the 2 to 1 produces more top end power. I've got Bassani power curve true dual headers with the megaphones. This pipe is unique. both header pipes are the same length and volume. they perform almost as well as the top 2 into 1 headers do.

 

fwiw

http://www.harley-performance.com/harley-exhaust.html

 

Lot of conflicting claims in the posts above.

1. The stock HD head pipes and slipons are not a bad combination for stock engines. Produce decent gains in most cases and the torque band is ok
2. Going to true duals on a stock bike will lose you some bottom end grunt, but will you feel it, maybe
3. True duals , especially Rineharts perform better on larger engines. There is nothing wrong with running true duals if you are happy with them, but if seeking the last ft lbs of torque an engine may have, you will get it with a 2 into 1
4. There is not a true dual out there that will outperform a good 2 into 1 for torque in the lower rpm ranges
5. A good 2 into 1 will make torque lower in the rpm range, but may also sacrifice some hp up top, nature of the beast.
6. The Bassani Power Curve is a good pipe, but it will not outperform a good 2 into 1 for torque in the rpm ranges that you normally ride. True duals will usually outperform 2 into ones at the very top of the hp range.
7. If true duals were a better performance pipe, then why would anyone that has invested huge sums of money in engine builds not run them? Some do, but the vast majority dont. There are a ton of dyno sheets on varius sites, Latus, Nightrider, etc. Review them and then make your choice. Lots of people make decisions on looks and sounds, not performance, and there is nothing wrong with that, but us power junkies will run mostly the two into ones unless at the dragstrip, where duals make sense for making high end hp.

All this being said, it is an individuals choice, and this debate will go on for years.

 

Im not sure. I bought my TH cuz it looked cool!!!