2-1 Debate

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Oct 19, 2011 | 11:14 PM

Barry Powers

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2-1 Debate

So looking to change from the shortshits (not a typo) to a good 2-1exhaust. What performs better VH comp, LSR Pro Stock, or the DDBobcat? Or do you guys have any other suggestions out there?

Oct 20, 2011 | 05:37 AM

grbrown

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From: Bedford UK

The only one I have direct experience of is the SuperTrapp SuperMeg on my Glide. I dynoed the previous system and the SuperMeg and got over 10% more torque in the low/mid range, also the motor is much smoother and sweeter running. So I am pleased with mine and suggest it is worth looking at the Sporty version. I will certainly consider getting one for my SuperLow (too many 'super' in this post!) when the time comes.

Oct 20, 2011 | 06:03 AM

WildThang

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From: Bonaire, Ga.

Will pay a little bit...but if you truly want performance, consider the Bobcat...also it makes the sporty look and sound badass...

Oct 20, 2011 | 06:34 AM

FBFletch

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From: Hickory, NC

Quote:

Originally Posted by Barry Powers

So looking to change from the shortshits (not a typo) to a good 2-1exhaust. What performs better VH comp, LSR Pro Stock, or the DDBobcat? Or do you guys have any other suggestions out there?

Funny you should bring this up because I'm trying to make the same decision.

Read everything you can about all the exhausts that interest you and at the end of the day, you'll probably conclude that, in general, the best performing exhausts (in the opinions of their owners) are R&B Racing, Thunderheaders, D&D Fat Cats, and V&H Pro Pipes. However, you will NOT find a definitive answer as to which is best because there is NO empirical data to back it up. The exception to that is that there is empirical data to support that a 2 into 1 exhaust performs better than a dual exhaust including those with crossover pipes. Beyond that, it's all just a matter of opinion as to which 2 into 1 exhaust is best.

How ANY exhaust performs for your bike is based on the length and size of the primary tubes, the length and size of the collector, how those match to what your heads will flow and the cams you're using, and what kind of performance you're looking for. So, there's really too many variables to say that one specific pipe is THE ONE unless you try every single pipe available on the market. And, unless you just bought a winning lottery ticket, that's not really feasible.

It's my opinion that there's little difference in what exhausts of similar design (primary size and length, collector size and length) are capable of.
The only thing you can do is just pick one you like, tune with it on a dyno, and experiment with different baffles until you find one that matches the exhaust to the flow of your engine (based on what the torque curve is doing).

But that's just my opinion.

Oct 20, 2011 | 03:20 PM

fourburgs

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From: Lansdale Pa.

I am running Phython 2 into 1 on mine and I love it..

Oct 20, 2011 | 05:41 PM

Barry Powers

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Thanks for all the great ideas. The python and supertrapp are too long for my liking. WildThang you notice a big difference in performance with the Bobcat? And FBFletch are you saying the shortness of the VH Comp pipe is going against having a 2-1 because it's not giving you the full experience?

Oct 20, 2011 | 06:14 PM

FBFletch

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From: Hickory, NC

Quote:

Originally Posted by Barry Powers

I'm no expert on all the pipes you've mentioned. But from the research I've done so far I think the only one that you mentioned that might not be a good choice would be the LSR Pro Stock. As I understand it that exhaust is really meant for large displacement drag bikes (113 cu in or bigger). But I could be wrong.

Supposedly, for every bike (actually every engine) there's an optimal length of pipe based on that engine's flow capabilities. Get the pipe too long and there's too much resistance which will adversely effect your top end power. Get the pipe to short and it won't scavenge properly and it will adversely effect your torque. Baffling has a similar effect and changing to different baffles effectively changes the length of the pipe (by changing the resistance to flow).

You get a similar effect with changing the diameter of the pipes. The larger the diameter pipe the more freely it flows and the more top end horsepower you can make. However, your mid-range torque is going to suffer.

The problem is finding the right length and diameter exhaust for YOUR bike. Again, about all you can do is just pick one and then match it to your engine as best you can by experimenting with different baffles.