Dyno results with duals to 2-1. Shocking!
#22
10-28-2012, 01:10 PM
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If you look closely the 2:1 did make "more" torque; maybe not a higher peak value, but it came on a little earlier and carried out a little further than the dual, so a wider torque band means more total torque across the RPM range. I was kind of surprised to see it carry further. Besides the WOT representation here, I would be curious as to the overall performance and drivability comparison at the lower operating range. While the results presented here may seem compelling, they should be considered carefully, the RB pipe has relatively short primary tubes as compared to the duals, and the low/mid 48 cam will respond better to the longer primary system. Do the same comparison with a mid/high cam and performance will lean in the favor the RB pipe. It would be interesting to see what a long primary 2:1 produces on the same bike, like the Fat Cat or Dragos. Even if another pipe produced better results, it still wouldn’t mean that pipe is the best for all bikes, it just worked best on that particular bike. The topic of exhaust is an emotional one for most, not all duals are the same and not all 2:1s are the same, you have to break down the details of the design of an individual system and match it to your cam, displacement, and riding style, too bad those critical details are not published by most manufacturers. Unfortunately most people buy their exhaust based on appearance and sound, with performance being the last priority. A lot of people want to believe the duals are better but there is simply no denying the performance benefit of scavenging achieved by a merge collector, no matter how you slice it. Is it possible that a specific bike can produce better results with a particular dual system than with another particular 2:1 system, sure? With all the variances in primary tube diameter and length, let alone muffler characteristics, it is nearly impossible to have a fair comparison among different production systems. Finding the "perfect" exhaust for your bike is a challenge for sure and one that usually takes a lot of trial and error and wasted money, regardless if your exhaust priority is appearance, sound, or performance.
I wondered what a Drago or V&H pro pipe would do on the dyno, just to compare. But I'm happy with what I have, and done spending money "just to see what happens"!
#23
10-28-2012, 03:15 PM
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#24
10-28-2012, 08:23 PM
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#25
10-28-2012, 09:30 PM
From what Ive read in a lot of places the Rinehart extremes true duals make good power, I wonder what the differance might have been with a different headpipe true dual going to a 2-1? The Rinehart extreme have a larger diameter headpipe compaired to most other headpipes. Thtas why even though the pipe covers my oil and trans fill ports I havent traded to a different exhaust. Enjoy your new 2-1, does it at least feel stornger? Hows the sound compaired to the duals?
#26
10-29-2012, 09:18 AM
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From what Ive read in a lot of places the Rinehart extremes true duals make good power, I wonder what the differance might have been with a different headpipe true dual going to a 2-1? The Rinehart extreme have a larger diameter headpipe compaired to most other headpipes. Thtas why even though the pipe covers my oil and trans fill ports I havent traded to a different exhaust. Enjoy your new 2-1, does it at least feel stornger? Hows the sound compaired to the duals?
#27
10-29-2012, 09:50 AM
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#28
10-29-2012, 11:24 AM
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#29
11-30-2012, 09:51 AM
Road Warrior
I have found out something similar in my quest to an answer of a question on my own: Which is better, a 103 with heads and cams, or a 107 with cams and stock heads?
What I am finding is, while the cost of both are very similar, and the "peak" numbers are similar, the range of the Torque on the 107 setup is broader than the 103 setup, someone please correct me if I am wrong.
A dyno sheet is just a representation of how the bike was running that day, in those ambient weather conditions, at a given location. It's more important to look at the sheet and see how it matches your riding style rather than focus on "peak" numbers.
There are a lot of guys charging people a lot of money for dyno tuning just to show them good numbers at WOT, peak numbers. Few people (although they are out there) will tune your bike in the places you use most (i.e.: not WOT). I still have yet a lot to learn about all of this, but this quest for power and doing it the right way, has been very educational. It serves people well to educate themselves when embarking on all of this performance stuff, if not you can very easily get taken for a ride, or be sold a setup that someone may like to build, but does not necessarily match the way "YOU" ride.
Just my $0.02
FM
#30
11-30-2012, 06:42 PM
Road Captain