Hey Steve is the problem with the cores or the head pipe. Can you just add torque cones to help with the curve and bottom end? Just asking for additional info. I love the way this pipe looks and sounds.
When it comes to accellerating heaving objects like Harleys, more low end torque is always better. Especially if the object has a fat bald guy on it like mine. Best TQ curves are a made when the headpipe and mufflers work as a team. When the 1.75 "headpipe suddenly opens to a 2.5" muffler core, the high pressure wave slows dramatically on its way out of the muffler to the point of it being in the way in of the next one coming down the pipe. A bandaid can't fix that. A smaller 2" louvered core that has an ID close to a 1.75 straight tube will keep air speed high and maintain the momentum of the pulse to the end of the pipe. Everything has to play together. TQ cones are an old school trick that helped sooth tuning ailments on carbed bikes with overly large and short exhaust systems by limiting the amount of reversion that could actually travel backwards through the exhaust port and out the carb. With todays EFI and 02 sensors being central, the TQ cones would need to be downsteam of the 02 sensors to keep them under presure. Any exhaust that actually benefited from adding a resticter would have to be way out in left field in terms of being sized right.The V+H mufflers do exactly what they were designed to do, play a very deep smooth exhaust note. The compromise is less than optimum low end power, and for many that's no big deal. But for fat bald guys it is a big deal. Riding in the back is not an option.
I hope this info helps.
Steve@fullsac.com
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Topic: Vance and Hines HO on new bike. (Read 4471 times)