Need Help Reading a Dyno Power Run
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Outstanding HDF Member
Joined: Apr 2009
Posts: 2,582
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From: Central Jersey
Need Help Reading a Dyno Power Run
I installed a SE255 cam, Vance and Hines Dresser Duals and Monster Oval, Stage 1 AC and a PC-V. I have a canned map from FuelMoto. I let my dealer do a power run just to see if I was running too rich or lean. After the results they said I could still use a complete Dyno Tune. Can anyone look at my power run and tell me if it's worth the money for a Dyno or is the canned map look ok. My gas milage is around 32 mpg...but that's getting heavy on the throttle from time to time.
Outstanding HDF Member
Joined: Nov 2006
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From: Mass
...you should Dyno it in my opinion..your TQ line shows a problem between 2700 and 3300 or so...remember, a perfect TQ and HP line would be rock solid straight no matter at what angle...your TQ line is pretty shaky...
Extreme HDF Member
Joined: Sep 2008
Posts: 15,259
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From: Delaware
the shaky lines indicate a problem with the air/fuel mixture. Something a good dyno tune can correct. In addition, I think, with the cam, you should be pulling more power than that. Normally, I'd say you're lean and that is the cause of the problems. But, your mileage suggests you are running rich. That could be your A/F issue. In short, yeah, spend the extra 200 or so and get a good tune done. Before you go back to this dyno, check the DJ web site for a tuner in your area.
Ultimate HDF Member
Joined: Nov 2008
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The numbers aren't bad but with your setup, I think you can gain a little more judging by other guys running the same setup and looking at your A/F ratio. The small dip on the tq curve could be attributed to the true duals. That being said, I know a guy running 255's PCV with auto tune and true dual on an 08 flhx and he pulled 83hp and 111tq. Of course every motor is different and so is every dyno. Temp and other things play in to dyno runs also. I do think you have room for improvement, you just have to decide if the cost of the tune is worth the gain you are leaving on the table.
Advanced
Joined: Aug 2009
Posts: 66
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From: Highlands Tx
If it was mine I would want it tuned. The dotted line is 13 AFR and you are running in the 14s and up to 15 at 3500 rpm then it eases back down to 14.
I wish they would scale the AFR graph to something like 10 to 18 and it would make it much easier to see on the AFR graph. I have messed around with WinPep7 and this is possible. It would give a better resolution.
I wish they would scale the AFR graph to something like 10 to 18 and it would make it much easier to see on the AFR graph. I have messed around with WinPep7 and this is possible. It would give a better resolution.
Road Warrior
Joined: Nov 2007
Posts: 1,800
Likes: 307
From: Houston, Texas
I know very little about reading dyno charts but shouldn't the RPM cut out be over 6100 with a stage 1?
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Ultimate HDF Member
Joined: Nov 2008
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If you look at his dyno chart again, you'll notice that the bike has stopped increasing power at around 5300 rpm. There's no point in running it up to 6100 rpm when it already stopped increasing power.
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Road Captain
Joined: Feb 2009
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In short.........yes, this bike needs to be dyno tuned.....by somebody that really knows how to "performance" tune.
This isn't even a good canned download in my opinion. Look at the power curve (or in this case, lack of it)......it's terrible. Spend the money for a good tune and you'll be a happy camper.
Take a look at your power curve and the power curve of my wife's dyno sheet and you'll see the difference. A good tune should be a smooth, fluid arch....with the top of that arch between 3,000 and 5,000 rpm.
There are many others that will have higher peak numbers (spiked) but you want it across the power band, not just in one spot. Few will have a power band as smooth as this one.
We're in California.......you're going to pay more than a couple hundread for a dyno here....especially with somebody that's good.
Good luck. Show us the "after" dyno sheet when you get it tuned.
This isn't even a good canned download in my opinion. Look at the power curve (or in this case, lack of it)......it's terrible. Spend the money for a good tune and you'll be a happy camper.
Take a look at your power curve and the power curve of my wife's dyno sheet and you'll see the difference. A good tune should be a smooth, fluid arch....with the top of that arch between 3,000 and 5,000 rpm.
There are many others that will have higher peak numbers (spiked) but you want it across the power band, not just in one spot. Few will have a power band as smooth as this one.
We're in California.......you're going to pay more than a couple hundread for a dyno here....especially with somebody that's good.
Good luck. Show us the "after" dyno sheet when you get it tuned.