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[charles05663]

After seeing all of the posts post of dyno results I had to find out what Petunia would do.  After seeing the results, I am not sure what to think and would appreciate some suggestions to produce a flatter torque curve.

Modifications:
Catless header
Fullsac 2" baffles
TTS Mastertune

I started with the Fullsac map and performed 3 tuning runs with the bike for a total of about 220 miles.  I do note that the best performance is in the center of the RPM range where most of the driving took place.  I wish that I had my computer with me when I had the dyno done.  It would have been nice to pull some data from the bike and produce another map.

From what I see, the HP curve is well defined and what I would expect.

The guys who did the dyno were shocked at the results and was wondering what was done and could not believe that it only cost about $700 to pull the top numbers.  They then tried to sell me a package for about $3500 to add some more torque.

[Dan_Lockwood]

Charles, I'm a little confused.

Your graph is a split graph with HP and torque on opposite ends with a different scale, but the rpms are constent for bother HP and torque scales.

In ALL dyno charts, HP and torque intersect at 5250 rpms.  Torque is what the dyno reads and compares that to rpms.  The dyno then does a calculation that arrives with the HP from the rpm and torque readings.  Torque times speed equals HP.

Why does you graph have them intersecting in the mid 4k range?

Can someone explain this to me please?

Just curious why.  The actual numbers look very close to what others with this combo have produced, so the numbers are not in question, only the graph.

Curious minds would like to know.

Thanks and have fun with that great bike.

    

[ssls6]

The scales are different which makes the intercept between HP and TQ look funny.  If you read the HP curve at 5250 rpm, you see it's a max at 93.  Now you can slide down until you hit the TQ curve.  At that point it is also 93.

[charles05663]

Thanks Dan and ssls6

I did not notice/register to me the different scales on the chart.  After looking at it again, it makes more sense to me why the torque is bell shaped and not flat like the others.  Most of the other dyno graphs posted are using the same scale on both side.

I am planning on getting some more vtunes done in the spring and see if I can improve the overall performance.  I was really surprised how much better the bike performed with each iteration of the map.

Love the TTS!

Charles

[Dan_Lockwood]

The scales are different which makes the intercept between HP and TQ look funny.  If you read the HP curve at 5250 rpm, you see it's a max at 93.  Now you can slide down until you hit the TQ curve.  At that point it is also 93.

SSLS6, you are so very correct.  It all matches up when you go up from 5250 but use both scales.

Thanks for bringing that to my attention.

 

[Unbalanced]

Charles the numbers are right you just need to ask the dyno tuner to print out your map in Forced Scale.  That will resolve the issue.

The only thing that I would question is the tune down low below 3000 rpm.  There should be more torque there early on.

Here is a dyno for a 110, TTS, FullSac 2" and Open Air Breather.  While not done on a dyno jet, this is what your curve should look more like only slightly higher numbers about 8 - 10 percent higher on the dynojet.

[charles05663]

Thanks unbalanced,

I was wondering about that.  When I vtuned the bike, most of the changes were in the center of the VE tables.  I figured I need to find some hill I can open Petunia up in 1st gear.  Next time I will have them force scale the chart.  I would think that was standard based upon all of the other charts posted here.

Charles

[Unbalanced]

Charles,

Usually (forced scale) is the standard,  but when people upgrade software and such the defaults sometimes need to be reset.  Its really not a big deal although some people who dont know any better make it into a big deal, its not the numbers are the numbers.  It is easy to recognize as your left column is at a 100 and your right column is at 110.  Forcing it to scale keeps both columns even.  If you do the math at any point you will find your hp works out right.  Just looks a little odd is all.  Tuning sounds like a good excuse to go for a ride and have some fun

[bob2002]

Is that a 4th gear pull? I'm no expert but aren't 5th gear pulls the norm?

[charles05663]

I thought it was a 5th gear pull.  Does it mean that it is a 4th gear because it says:
CF:SAE Smoothing: 4 ?

[bob2002]

Like I said I'm no expert but I think so,I wonder if that gives higher numbers then it would in 5th.Does anyone know for sure?

[Unbalanced]

typically 4th gear will give slightly lower numbers vs. a 5th gear pull.

Depending on the tuner most pull in 4th gear on a 5speed and on a 6 speed they will pull usually a 4th and a 5th gear.  

Smoothing is just correcting the curves it helps smooth out the lines to not make them quite so jagged.  You can smooth from 1 to 5 on a dyno jet print out.

Typically to get the nicest looking you will see someone do it in Smoothing 5 just because it shows the best.

Normally you will see dyno print outs in   STD / SAE and once in a while uncorrected depending on who is doing the dyno. 

Edited to remove the word SAE.  Thanks for catching that Ed didn't proof it very well .



 

[eddfive]

Hold the phone here.  SAE is a universal correction factor for standardization.  Smoothing is un-related but smooths the curves SAE and Smoothing are different things.

The following article explains the SAE standard for a dyno and why it is used for standardization.  There is also other standards that can be used but SAE is one way of making the data across the country mean something.

http://www.land-and-sea.com/dyno-tech-talk/corrected-horsepower.htm

Smoothing is just smoothing out a curve or removing the jagged edges.  I usually like to keep my smoothing number at 1 so I can get a real feel for what the bike is doing during a pull.  Peaks and valleys in a curve can mean something is not right in a tune with either fuel or ignition if you pay attention.  Smoothing out the curve to 4 or 5 "masks" over this information.  The devil is in the details.

[HD Street Performance]

Use your TTS and do some logging
You may find the Delphi is pulling out timing at the low end and timing tables may need adjustment.
No AFR trace on the graph either. Would wonder if the VEs got set right and it is back in closed loop.

[Herko]

Hold the phone here.  SAE is a universal correction factor for standardization.  Smoothing is un-related but smooths the curves SAE and Smoothing are different things.

The following article explains the SAE standard for a dyno and why it is used for standardization.  There is also other standards that can be used but SAE is one way of making the data across the country mean something.

http://www.land-and-sea.com/dyno-tech-talk/corrected-horsepower.htm

"SAE is SAE."

No, not always. All of the air density,weather and run condition etc. can be factored in, but the applied algorithms and configuration files for the drum mass (drum and brake mass on load cell models) can make a difference on the output numbers.

One example: If the drum on a dyno weighs only 500 pounds but the algorithms and configuration file for that dyno are based on a 600 pound drum, the HP and TQ numbers will read high. An average build can look like a hero when spinning up a drum that has lighter actual weight vs. stated weight. The 500/600 numbers are rounded and broadened. But, a few small algorithm numbers erring to the wrong (or right) direction can make a big difference on output.

Dyno manufacturers obviously configure their dynos and software to display what they think is "right"...i.e. their dyno is accurate and should be the standard. It's no big secret that what a manufacturer thought was right during the making of their early dynos and what they think is right for today's dynos could very well be different.

Another area that software design can make outputs show different is in AFR sensing devices.
When using a test gas for the purpose of O2 sensor calibration checks, the displayed AFR of system A vs. system B can be off 2 to 3 tenths (or more) when two identical sensors are in the same test manifold receiving the same gas. When sensor leads are switched to from sys A to sys B, the offset remains with the software... meaning if sys A read low before it will read low again even when connected to the sensor that read higher moments ago.

Each manufacturer makes inputs to the software to display what they think is right, but devices (including Dynos) from one manufacturer to another...or from the same manufacturer but from a different era can read differently...even when "SAE" is used as a correction factor