The muffler itself is an open pass through to all four exit pipes so the rear valves would cut down the sound when closed leaving only two exit pipes. But what look like primary valves cut off half of the incoming flow to the muffler which I don't understand. Maybe the muffler can't handle the flow from two inlet pipes when only two exit pipes are open? There is an h-pipe up front past the secondary cats and an x-pipe at the rear in front of the primary valves. Is this balancing upstream scavenging and rear back pressure? However this was engineered would be interesting to understand. Sounds quite sophisticated. Any feedback or thoughts on this?
Primary and secondary exhaust valves on V3s?
I decided to buy a Borla cat-back and am looking at the overall system noticing what look to be primary and secondary exhaust valves for changing from touring to sport/track mode. I haven't seen this in discussions to date which have been focusing on primary and secondary cats. I'll be doing the install in a few weeks but anticipation is driving me to check here in advance.
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I honestly don't know what to make of that pic... my 2019 doesn't have those upstream valves - it looks identical to this one below. Not sure why there would be valves that can close and shut off the exhaust flow completely, other than some sort of sound/backpressure tuning thing they seemingly did away with quickly.
Is that pic of your car? Or is it some pre-production marketing/concept pic? I bet your car doesn't have that, which is why you can't find any discussion history.
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Is that pic of your car? Or is it some pre-production marketing/concept pic? I bet your car doesn't have that, which is why you can't find any discussion history.
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