Got Dyno results, need feedback
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Got Dyno results, need feedback
I got the sporty dyno tested last week. Results were: Horsepower- 47.6, Torque- 48 ft lbs., fuel/air mixture- 13.4
I was also told there was a dip in the torque graph upto 4000 rpm, and placing baffles in the pipes to increase back pressure would bring the torque band up, providing a quicker response time when accelerating and under 4000 rpm. (not sure of terminology and if all that makes sense, but that is how I remembered the explanation)
The bike is a '93 883xl with 1 3/4 inch drag pipes,no other mods.
What do you guys think? Are these results standard? Can I make some minor efforts for performance gains?
thanks.
I was also told there was a dip in the torque graph upto 4000 rpm, and placing baffles in the pipes to increase back pressure would bring the torque band up, providing a quicker response time when accelerating and under 4000 rpm. (not sure of terminology and if all that makes sense, but that is how I remembered the explanation)
The bike is a '93 883xl with 1 3/4 inch drag pipes,no other mods.
What do you guys think? Are these results standard? Can I make some minor efforts for performance gains?
thanks.
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Joined: Jul 2007
Posts: 2,192
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From: Metro Milwaukee, WI
RE: Got Dyno results, need feedback
Some type of baffles would help for starters, Second I'd be looking into a high flow air cleaner and a carb rejet.
If you are willing to part with a little more coin, Bassani Pro Street exhaust will be a nice upgrade as well
Drag pipes on a streetbike just rob low end power and torque. A quality step tuned exhaust would help alot.
If you are willing to part with a little more coin, Bassani Pro Street exhaust will be a nice upgrade as well
Drag pipes on a streetbike just rob low end power and torque. A quality step tuned exhaust would help alot.
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Joined: May 2005
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From: A barrier island in NJ
RE: Got Dyno results, need feedback
Ditto with Biker Trash - for the most part. Baffles are a must for needed back pressure and reversion. Drag pipes are made for top-end improvement - period (and lots of annoying, i.e., not particularly classy, noise). Drag pipes are definitely robbing you of torque and your hp number seems lower than it should be. Bassani Pro Street exhaust is certainly an answer and they're nice pipes, but for a lot less money you can improve torque and hp with the addition of Big City Thunder Baffles at a fraction of the cost, and move your torque and hp to the low and mid-range where 98% of riding is done.
Check 'em out:
http://www.bigcitythunder.com/pages/...rformance.html
Check 'em out:
http://www.bigcitythunder.com/pages/...rformance.html
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Joined: May 2005
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From: A barrier island in NJ
RE: Got Dyno results, need feedback
ORIGINAL: Terp84Alum
Good advice given. I would add that your performance would probably be better if you could find your stock pipes.
Good advice given. I would add that your performance would probably be better if you could find your stock pipes.
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Joined: Dec 2007
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From: Phoenix, AZ
RE: Got Dyno results, need feedback
ORIGINAL: Sp0rtster
Results were: Horsepower- 47.6, Torque- 48 ft lbs.
there was a dip in the torque graph upto 4000 rpm,
'93 883xl with 1 3/4 inch drag pipes,no other mods.
Results were: Horsepower- 47.6, Torque- 48 ft lbs.
there was a dip in the torque graph upto 4000 rpm,
'93 883xl with 1 3/4 inch drag pipes,no other mods.
Drag pipes will give you better numbers at the very highest rpm but suck at lower rpm. We summ it up by calling it "back pressure" but it is a complex problem of the air leaving a cylinder: compressible fluid dynamics of a pulsating flow.
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RE: Got Dyno results, need feedback
Thanks for the feedback. I believe I mis spoke. The jets have been changed and there is one of those forced air, triangle shaped air housings over a K&N air filter. I think they call it a "hyper charger"?
Regarding the rpms, it picks up at 4000 rpm. It is below that the torque dips down.
I appreciate the feedback on the exhaust. I have heard of the Bassani Pro Street, but will look into the Big City Thunder Baffles.
Can anyone elaborate on what the ignition upgrade entails? I see stuff on "Screamin Eagle", but what does that do for the bike's HP or Torque or anything?
Regarding the rpms, it picks up at 4000 rpm. It is below that the torque dips down.
I appreciate the feedback on the exhaust. I have heard of the Bassani Pro Street, but will look into the Big City Thunder Baffles.
Can anyone elaborate on what the ignition upgrade entails? I see stuff on "Screamin Eagle", but what does that do for the bike's HP or Torque or anything?
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RE: Got Dyno results, need feedback
I'm not sure of the benefits,but I have a Screamin Eagle coil,wires,and plugs setup.It was given to me by a friend.But like I said I don't know the benefits.If someone could tell me that would be great.
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Joined: Apr 2007
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From: Appling GA
RE: Got Dyno results, need feedback
Standard thinking is it adds around 5HP
Stage 0: Stock
HP=40 for 883, 50 for 1200 (average) [hr] Stage .5 (also known as "The Harley Tax"): Stock plus:
SE Air Cleaner
SE Slip-On Mufflers or equivalent
Rejetting
HP=50 for 883, 60 for factory 1200[hr] Stage 1: Stage.5 plus
883/1200 conversion
SE Ignition Module or adjustable one
HP=60 for 883/1200, 65 for factory 1200
Stage 0: Stock
HP=40 for 883, 50 for 1200 (average) [hr] Stage .5 (also known as "The Harley Tax"): Stock plus:
SE Air Cleaner
SE Slip-On Mufflers or equivalent
Rejetting
HP=50 for 883, 60 for factory 1200[hr] Stage 1: Stage.5 plus
883/1200 conversion
SE Ignition Module or adjustable one
HP=60 for 883/1200, 65 for factory 1200