Equal Exhaust Pressure
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Stage III
Joined: Nov 2015
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From: Cornelius, NC
Equal Exhaust Pressure
I have a 2016 FLHXS with Freedom Performance True Dual Headers and 4" slipons. I had HD install a SE breather and remap the ECM. I do not have equal exhaust pressure out of the end of the pipes. This is an issue because of some special mechanisms I want to install instead of tips. Does anyone know why I would not have close to equal exhaust pressure, or at least close, on each side?
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with a single pipe to each cylinder you will ( or should have) equal volume of exhaust gasses- the pressure may be affected by uneven header length and cooling of the gasses within the headers.
header length and cooling of the gasses will also affect the velocity within the pipe.
add cam overlap and duration and you may get differing results at idle and 3000 rpms
I can only guess that even length headers which are jet coated or wrapped ( to retain heat) would give you closer to the result you'd like.
this equal length of the rear header pipe is why bassani marketed the "power curve" which added pipe on the rt side of the bike...problem was you couldn't get to the oil or tranny fills.
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Mike
header length and cooling of the gasses will also affect the velocity within the pipe.
add cam overlap and duration and you may get differing results at idle and 3000 rpms
I can only guess that even length headers which are jet coated or wrapped ( to retain heat) would give you closer to the result you'd like.
this equal length of the rear header pipe is why bassani marketed the "power curve" which added pipe on the rt side of the bike...problem was you couldn't get to the oil or tranny fills.
to get a moderators attention, click on the yellow triangle at the top right of a post
Mike
Last edited by mkguitar; Nov 8, 2015 at 11:10 AM.
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With true-duals the only way your exhaust pressure is going to be the same out of both of them is if the pipes are the same length. What are these special tips you talk of?!
Last edited by grbrown; Nov 9, 2015 at 03:13 AM.
The difference is so minimal you can't tell the difference.
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Yep, plus they take different paths. On V&H dresser duals for example, the rear cylinder exhaust has a lot more sharp turns than the front.
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Stage III
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From: Cornelius, NC
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