Pro pipe 11hp loss

Discussion in 'Engine, Fuel and Exhaust' started by Brutal FXDX, Oct 14, 2010.

  1. Brutal FXDX

    Brutal FXDX Active Member

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    Has anyone lost power from inst a 2-1 V&H propipe?? Ive got a 2009 FLHX here at the shop that i inst a SE 103 stage 4 kit back 9 months ago. Bike made 113hp and 107 ft/lbs with V&H power duals with rinehart slipons tuned with SE super tuner. Today cust brought me a propipe 2-1 to inst in place. After tuning it made 102hp and 93 ft/lbs. I just dont understand why. Anyone??
     
  2. Jack Klarich

    Jack Klarich Expert Member

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    I would have thought better scavenging for more power with the new pipe?
     
  3. Brutal FXDX

    Brutal FXDX Active Member

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    My thoughts the same Jack. Ive inst. a number of different 2-1 pipes on everything from stage 1 up with gains in hp and tq. this is the biggest build ive installed a propipe though. Just dont understand the 11 hp loss. Anyone tried the RB racing LSR 2-1. Heard they are very good 2-1.
     
  4. maine-e-axe

    maine-e-axe Junior Member

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    Gaskets next to the head can choke it down alot when clushed.
     
  5. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    Did you do a baseline run before you changed to the exhaust, or did you assume the engine still had the same HP?
     
  6. Brutal FXDX

    Brutal FXDX Active Member

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    No did not do a baseline. Think im putting on the old pipes today and try it out.
     
  7. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    There are a lot of factors that can change dyno runs. I've seen the same bike produce different #s with a change in the temp or moisture in the air. While your looking at a large drop from an initial run some time ago, some of the parameters of the dyno may not be the same. I would think that with the 2 onto 1 you should see increased torque and HP.
     
  8. Hoople

    Hoople Account Removed

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    To add along with what HDDon said,, software used on inertia dyno's is not perfect. Be sure that the numbers are "corrected" for the settings of the day during which the pulls are taking place. If they are Not measuring intake temperature, baro pressure & humidity, it could easily explain the differences in numbers. Those numbers should be "corrected"

    Most of the Dyno's that are used are not pony brake or true torque arm dyno's which will produce accurate numbers. They are software calculations of the inertia of the spinning drum. Therefore the correction factors really come into play.

    Good Luck with your numbers!:)