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Discussion Starter · #1 ·
I've done various google searches but couldn't really come up with any real definitive answers.

How is it done? I'm assuming some sort of software running on the dyno, mixed with data received from the ECM and/or sensors that are strategically placed on the bike? Can I still use a closed-loop bias to determine my desired closed loop actual AFR?

Since I use Mastertune, would a tuner be able to determine these VEs, then give me an accurate VE table that I can then load myself, using the same CLB numbers?

Just trying to clear up some unknowns, thanks for any info!
WP
 

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WickedPorter,

The question you pose leads me to wonder how you've been tuning your motorcycle thus far. It's kind of essential that you understand what the Volumetric Efficiency is in order to tune your motorcycle correctly.

Read mjw's link HERE. It gives the definitions of the abbreviations commonly used with dealing with the delphi ECM.

The definition of Volumetric Efficiency is in there. Once you can understand the definitions, you'll be able to see that by manipulating the VE table, you are providing the ecm with the data it needs to meet the fuel requirements at any given rpm at any given map. It is by sampling the AFR that we make the determinations on changes to the VE table and thereby obtain the optimum tune.

Personally, I don't have a bike that uses a closed loop system, so CLB is something I haven't really gotten in depth with.
 

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Discussion Starter · #3 ·
WickedPorter,

The question you pose leads me to wonder how you've been tuning your motorcycle thus far. It's kind of essential that you understand what the Volumetric Efficiency is in order to tune your motorcycle correctly.

Read mjw's link HERE. It gives the definitions of the abbreviations commonly used with dealing with the delphi ECM.

The definition of Volumetric Efficiency is in there. Once you can understand the definitions, you'll be able to see that by manipulating the VE table, you are providing the ecm with the data it needs to meet the fuel requirements at any given rpm at any given map. It is by sampling the AFR that we make the determinations on changes to the VE table and thereby obtain the optimum tune.

Personally, I don't have a bike that uses a closed loop system, so CLB is something I haven't really gotten in depth with.
RJ, thanks for your reply. I'm very familiar with the definition of volumetric efficiency, and I've been (somewhat) tuning my VE tables using MasterTune's VTune application, to answer your question.

Let me rephrase my original question. What I want to know is, how is VE determined using a dyno? What is the process? I'll add: I've never personally seen a dyno being operated in my life, aside from in photos and on youtube, where no tuning specifics are ever really discussed.

I know how to (within reason) determine and set my VE tables based on what V-Tune calculates for me. V-Tune is using Delphi/ECM sensor input and mathematical algorithms get as close as it can within my riding range.

That said, how do you calculate it with dyno? Does the dyno use it's own computer algorithms/software based on sniffers and MAF sensors of some sort, or do I bring my own (MasterTune/SERT/PCV/etc.?) How does the dyno know about the existing ECM/Tune, assuming it has some sort of interface to the Delphi system or piggyback tuner? What is the process? Is it different for different dyno's?

Further, if MasterTune VTune can only tune my bike up to 6,000RPM (discussed here: http://www.1130cc.com/forums/showthread.php?t=142057), even if I go to a tuner, would I be screwed on anything above 6000 RPM since this is the tuner I use? Or would the dyno operator have their own software/method they use to exclusively determine VE tables that I can then program to my ECM with MasterTune for these higher RPMs that I can't hit with VTune?

Thanks,
WP
 

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I see where you're coming from, I think.

The VE isn't "calculated" per se. What you do is you run the bike, weather on a dyno, or on the street. For any given RPM, at any given "load" on the engine you actually MEASURE, the Air/Fuel Ratio.

Since the VE table shows the Volumetric Efficiency at any given RPM vs "load" then you can actually MEASURE the AFR, you then know weather you need to ADD or SUBTRACT Fuel at that cell (RPM vs. "Load.") If you need to add fuel to reach your target AFR, you increase your VE in that cell. If you need to remove fuel to reach your target AFR, you subtract VE in that cell. The software, weather you're using V-Tune in the MasterTune package, or Daytona TwinTec's Twinscan, will actually give you the correction needed for that cell to reach that target AFR.

So, I guess the answer is that it's not how you put the load on the engine (i.e. On the street, vs. on a brake dyno vs. on a dragstrip), it's whichever sampling device you are using that will guide you to create your VE table.

Since the Delphi EFI isn't a TRUE CLOSED LOOP ECM, there is no MAF. If we did have a MAF, then the tuning process would be much easier.

So I guess in summary, the VE that goes in any given cell in the VE table is a product of the current VE plus or minus the "correction factor" which is determined by the software that goes with witch ever sampling device you are using.

Now, the Twinscan is one device I've used quite successfully. The MasterTune V-Tune software works pretty well too. But it does have some limitations, which I'm sure you've already discovered. Dynojet has developed a dyno/gas anylizer/powercommander setup that is designed to work together.

The software that any given tuner uses depends on what they have available to them and how well they were trained on it. Anyone can follow the step by step. But true tuner will be able to work with any tuning software to get a good result.

If you are going to get a Dyno tune, then you need to make sure the Tuner is familiar with the software for the Master Tune. Otherwise, you'll end up paying for his education.
 

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The last point: The Master Tune is a great device for 90% of your needs. You can put on the pipes and run your bike on the street cruising comfortably knowing your bike is in a pretty good state of tune. You can change pipes, or air cleaner, or cams, or what ever and just hook up your laptop and sample, tweak and ride happy.

What you can't do, is grab Wide Open Throttle because it limits the changes to 6,000RPM and lower. (Which by the way is well above the redline for Air cooled HD motors.)

Remember, the Dephi ECM in our V-Rods is a direct product of the HD air cooled line of motorcycles. All the support you're going to find, and all the "tendencies" you'll find with any of the devices available to us are geared for that large market segment. Anything that spills over to our beloved, but red-headed step child of the HD line we have to take as "bonus" material. The V-Rod segment just isn't large enough to support a whole lot of diversity in the tuning market, or the aftermarket in general.

So, if you want to tune the 6-9K Range, you need another sampling device. I use a Twinscan II plus from Daytona Twin Tech.
 

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Discussion Starter · #7 ·
That all makes sense and answers all of my questions. It makes sense that they would simply use a sniffer to determine actual AFR compared to desired AFR for given ranges to figure a VE offset/adjustment. Thanks for the excellent detail/information, RJ!

WP
 

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we really missed you RJ:popcorn: & subscribed
Thank you, sir. It's been a busy time in my life. All for the better though.
That all makes sense and answers all of my questions. It makes sense that they would simply use a sniffer to determine actual AFR compared to desired AFR for given ranges to figure a VE offset/adjustment. Thanks for the excellent detail/information, RJ!

WP
I'm glad you found it useful.
 
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