One Good "Pull" Deserves Another....

D

DAMN YANKEE

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Wow! What a great new resource for those interested sharing data about how to analyze logging data and to tune with a VEC!

As the intent is to share quality data amongst various VCA members, it seems to me the best place to start is in a broad discussion as to what constitutes a high-quality "pull". When I first began to experiment with my Vec3, I really did not have a good handle on what constituted a good logging "pull". After asking a lot of questions to a lot of different people, the began to clarify for me. Consistency and working with a properly prepared logging setup is of paramount importance. In fact, as more and more people begin to share their results it will become inherited that everyone use somewhat of a standardized, structured format. I have also taken the time to put the specifications for my Viper in my "signature". This allows anyone to know the general configuration is of my Viper. As we begin to look at some of the data from other members we have to know to some degree of the configuration of their Viper is.

I thought I would start a simple thread to share what I have learned about preparing a proper "pull" that results in a log that is of a high enough quality to use for tuning. I'll make a statement right on the onset, I am a street driving kind of person, I do not track or race my car. I also have a car with cast pistons, so I want a perfectly tuned car, putting out more than 500 horsepower but I am not looking to maximize every available horsepower. I am looking forward to reading what others have to say who have other expectations and goals for their Viper.

Perhaps the most important thing to do first is to prepare a default log that allows you to use the same log setup formats every time you start to do your "pulls". The VEC systems allow for you to set up your log master and then save it as a default. But before we save it as a default we have to be sure that we have properly set up the logging parameters. Anyone using a VEC needs to know right from the start that they do not have to worry about selecting the data parameters that will be logged. All data will be log and saved if you properly set up and, at the end of your run, either automatically or manually save your file. There is a caveat to this, one has to properly configured eight wideband sensor within the software. But, once that is done it too will be save each every time you use your VEC.

Be sure that you had accurately captured the weight of your car. This would include making sure that you have the same level of gasoline in the car every time you run a log. The best way I know to do this is to use a full tank gas every time. I use a weight of 3,720 pounds for my 2000 GTS, the weight of the car, the weight of myself and an additional 100 pounds for the supercharger. In a sense, the weight figure is most important to allow for a reasonably accurate horsepower and torque calculation. As long as your weight number remains consistent, you can see the relative changes.

Be sure that the gearing calculations are correct as well. The Vec software provides a gearing calculator, it is independent of the calculations used to actually drive the program so you can be confident to play around with it. What one does is to simply run your car up to 2000 RT and in any gear and make note of the actual road speed. Place that data in the calculation and see if in fact that results match the table found below. If they are at all close leave the default numbers as they are.

I also select the field at the bottom that allows for automatic saving without having to title the document. This makes it a lot easier when you try to drive the car.
Once you have all of the setup constraints properly addressed, go to the "settings" commanded the top of the page and save your logging document as the default. Always check to see that the right logging document as, prior to making your runs.

As to running an actual log in doing actual "pulls", I follow the following outline:

Find an absolutely flat piece of road that will allow you to go approximately 100 miles an hour.

I keep my logs relatively short, concentrating on a perfect single gear "pull". What this means is, I set by laptop in a seat next to me, with my properly configured default log ready to begin. I find a flat piece of road and without starting my log yet, I try to bring the car up to approximately 1,500 rpm and start the log. With a log running, I then naturally but very firmly push the accelerator all the way to the floor and proceed to run to 5,500 rpm. When I reach that rpm, I take my foot off the gas and allow the car to coast back to approximately 2000 rpm before I turned off the log. I should know that there are many who will simply allow their log to run for the full five minutes available to them within the VEC. Some have more logging capacity within their systems and will log for quite a long period of time. I think this makes sense once one is confident that their engine is in reasonably good tune. In the beginning, short, clean and controlled single gear logs make good sense. After that, a log that runs for two gears throughout the full rpm range makes sense. This is just the way I do it, I am sure and an looking toward reading the way others do it. To sum it up, for me, I run short, clean, single gear pulls.

There is quite a bit discussion on what gear is the proper gear to run logs. I use third gear, as fourth gear at 5,500 would be well over 100 miles an hour. It seems that tha majority of people that I talk to use third gear as well. So I can certainly see how using fourth gear would allow for a longer chronological data set. If I never find that much safe open road I will try it!

What also must be taken into consideration are the effects of "heat soak". As your engine begins to warm up, and the supercharger begins to warm up, there will actually be a loss of power. The more warm air is entes into the engine, the less gas it can support. For most people, the best results they will achieve in regard to horsepower and torque occur on cold days. That is the reason why we have intercoolers, that is the reason we use water and methane coolers. My Viper does not have to a methane cooler, so I try to do my logging in the coolest parts of the day and I try to capture my data before my engine becomes red hot and heat soaked.

When I first down to analyze my logs, I check the boxed the bottom that removes every indicator and then bring up each important indicator one at a time. Obviously, from a tuning perspective I most interested in Lambda Air/Fuel readings match against rpm. I would then bring up "power" or "torque" lines as well as the boost data. Folks, I don't know which is cooler for me...having my car run in top, top form...or knowing why and how my car got to run in top form...

What do you guys/gals do to prepare and execute a good "pull" and what do you concentrate on as you review your logs?

Lastly, we will have to find the best way to actually go about sharing data files. As you know this web site allows us to enter text and photos but does not yet support this saving and transfer of data documents. All of the files that I had actually shared with others, or they have shared with me, have been done through our separate e-mail accounts. This is going to be a slow way to get the job done
 
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KenH

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Good write-up. One thing I will add is that the note section is a good place to enter things such as air temperature, octane or other things which affected the pull or tune. Also a good spot to record the basic differences in tune from the last pull without having to go back and compare actual tuning tables.

I agree that it would be quite interesting to have a large repository of tunes and logging info to look at for different setups without having to email them around.
 

Mr Hemi Head

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DY where are the screen shots of your :drive: pulls already? You have been detailing this to death since:dunno: but we have yet to see the results of all this rhetoric. :omg: lol
 

GTS Bruce

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Sounds complicated.Do mods,dyno car with a/f.Send graphs and computer to DC.Get back in a week with improved idle,power,smoothness,fans on earlier,skip shift gone........
 
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DAMN YANKEE

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KenH, good points. Thanks for contributing! Sometimes I feel like I'm out here all on my own. I'm especially interested in seeing some results from you people with W/M kits and larger boost.

GTS Bruce, not complicated at all, so simple even a caveman can do it...There are some that will want to do their mods (or even have somebody else do them) and then send the results out to a 3rd party every now and have them send them back a file in a week. Its bascially the same thing, but one is understanding the tune and doing it all themselves, doing the tune when-ever they want, not touching their PCM (retuning for every new mod is possible immediately) and spending zero dollars. The reflash thing is great as it gets you your early fan and shift skip, but my fan works fine and the skip ship mods is a .50 cent resister. But I do get it. Having a good dyno is always a good idea every now and then, but you have to live near one. Mastering a good log and the resulting tuning may be the ticket for anybody that wants to do it themselves..Does DC give you some data you could post up? I'm curious to see just what their boost and A/F curves look like...

MHH,
Here is a nice clean shot of boost and another of the A/F at Open Loop. As this is a 5lb S/C, the boost came in right at target ( 5-7 ). Target tune for A/F was 11.9. For the unitiated, what we have here is a nice flat line oscillating between 11.4 AND 12.4. There is zero transition on this tune, in other words the shift from vacuum to boost is, well, like a rocket. The small pops up to the low 12s is perfectly fine and one could even tune that out, but the car rocks. MHH, do the patterns look like yours (I would imagine you are producing more boost)? Can one get a good flat line when producing 12-15 psi and providing shots as well?

Guys, thanks for geting basic specs (psi especially ) in your "signatures" as it sure help us get zeroed into what your world is.

Let the Game Begin....

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OP
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D

DAMN YANKEE

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MHH,

I know you will want the HP chart as well...I'll show you mine if you show me yours..

bts1.jpg
 
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grcforce327

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Twin __________________________________________________________________________________________________________________________________________________ 6000 :lmao:
Turbo
bts1.jpg
[/quote]
 

Mr Hemi Head

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There you go...especially like the last one.lol
The dyno chart is on my image gallery.
The log files went south with my hard drive so I don't have any to post at the moment.
I dont have the VEC 3 so no HP numbers.
Rick
 
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D

DAMN YANKEE

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Im always astonished at the number of corrections I have to make to my own text.

In the first part...
" There is a caveat to this, one has to properly configured eight wideband sensor within the software."

That should read " There is a caveat to this, one has to properly configure each wideband sensor with its software."

I use "Dragon Naturally Speaking" to lay all this text into these threads...no I do not type it all in by hand, I talk, it types.
Most of the time the rsults are great, but sometimes, a really interesting word gets in there!
 

SYNFULL

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However you are doing it- your write ups are just what I was looking for. Great work- I was wondering where I would be able to learn all the tuning dynamics.
Can you tell me how you set up the vec for the wideband. I read your writeup on wiring but I need the actual vec setting. I went into the log settings and if i am using AN-2 for the wideband what do I select in the sensor location- Is it Viper stock a/f?

Thanks
Gary

Im always astonished at the number of corrections I have to make to my own text.

In the first part...
" There is a caveat to this, one has to properly configured eight wideband sensor within the software."

That should read " There is a caveat to this, one has to properly configure each wideband sensor with its software."

I use "Dragon Naturally Speaking" to lay all this text into these threads...no I do not type it all in by hand, I talk, it types.
Most of the time the rsults are great, but sometimes, a really interesting word gets in there!
 

EllowViper

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I'll send some logs later in the week. Right now, I'm focusing on dialing in the Timing. I'm a bit dissappointed that I can't log the stock timing...only the timing offset (+/-) that the VEC is introducing. I'm wondering...how much timing are people taking out with their 5lb ROE set-up? In looking at Sean's basic Water/Methanol tune, he's taking out about 6-7 degrees until the W/M comes on. At that point, he's back to factory timing. I though that was real aggressive. :omg:Right now, I'm taking about 2-4 degrees out until 4000 RPM...and then back to stock, and then at 5000 rpm about 1-2 degrees out. I'm going to try even more aggressive timing later this week by bringing my W/M on earlier at a lower boost (1500 rpm @ 2.5 PSI). :dunno:I've built a nice little excell spreadsheet that shows my timing across the RPM and MAP ranges so I can quickly see what my timing is at any RPM/Boost setting vs. the computed stock timing.
DY keep up the great tutorials!!!:2tu:
 

PowerKraus

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I've recently posted in this tab (How to Share a Vec tune ? and Too late to the Party) concerning reigniting some activity for the very very few DIYers.

One of the main things that may push things along would be a central 'repository' for 'our' use to upload/download VEC tunes. I tend to get stuck on how to accomplish this via the web. I am sure many would appreciate some help on re-establishing a ftp site. Can you shed some light on this?

BTW, I am a heavy DIYer on tuning, with significant experience with HP Tuners, LS Edit, and EFILive from my years of running a juiced 408 stroker in my car f/k/a 2003 Vette (sold) and one of my other current rides, a boosted Grand National (30 psi), using a piggy back type system similiar in affectiveness as the VEC. I'd be more than happy to share my knowledge and contribute to the proper tuning of a fellow Viper's boosted ride. The VEC is a great piggy back type system that is a freaking Piece of Cake to tune. Which is wonderful. But I digress.

From the earlier posts of DamnYankee, seems he got this started, but it has since lost steam. The ftp site he mentioned appears 'dead' when I try to access it.

Hope to hear back, thanks !
 
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Fast Too

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Great thread. I'm interested in joining in on this, but I have a Gen 3 so my logs may not be of a lot of value to you gen 2 guys. I am working through some boost issues I am having which I discovered through logging. I should have the car back together tomorrow and plan to do some logging sometime over the weekend. DY I cracked up at your Y axis labels.
 

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