MSD 7531 graphs

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BigDog67
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MSD 7531 graphs

#1 Post by BigDog67 » Sat Jul 10, 2010 9:45 am

What are the steps to put multiple RPM recorded runs on one graph. I would like to compare at least two runs on one graph by over laying them if possible.

Thanks

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Re: MSD 7531 graphs

#2 Post by John_Heard » Sun Jul 11, 2010 4:38 pm

Big Dog - standby, I'm going to make a video to show ya how. It'll be easier to show you than explain it.

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Re: MSD 7531 graphs

#3 Post by John_Heard » Sun Jul 11, 2010 6:41 pm

Here ya go - let me know if you have any questions

http://www.screencast.com/users/idoxlr8 ... 2a620a1eb2

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Re: MSD 7531 graphs

#4 Post by 79 Camaro » Sun Jul 11, 2010 7:10 pm

John,
You have the coolest ways to show people how to do stuff.
That was bad ass :thumb:


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Re: MSD 7531 graphs

#5 Post by John_Heard » Sun Jul 11, 2010 7:25 pm

Glad ya liked that. Dang codec wouldn't work with Youtube, these dang computers are about as bad as race cars sometimes. I want to do another one showing how to drag a RPM trace over to a rev limit to set the curve for the dots, but need better software to do that one.

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Re: MSD 7531 graphs

#6 Post by BigDog67 » Mon Jul 12, 2010 6:52 am

John_Heard wrote:Here ya go - let me know if you have any questions

http://www.screencast.com/users/idoxlr8 ... 2a620a1eb2
Excellent!!!! Now for the second question, how can i do this but have it so i can move my cursor over it to compare RPM and time? Like on the Revlaunch graph.

On the "history file" is shows the X plane in time and the Y plane in a %. How can i get this so the Y plane shows RPM so i can figure out what my converter is doing.

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Re: MSD 7531 graphs

#7 Post by John_Heard » Mon Jul 12, 2010 7:54 am

BigDog67 wrote:Excellent!!!! Now for the second question, how can i do this but have it so i can move my cursor over it to compare RPM and time? Like on the Revlaunch graph.

On the "history file" is shows the X plane in time and the Y plane in a %. How can i get this so the Y plane shows RPM so i can figure out what my converter is doing.
MSD Doesn't let you change the X/Y Values in the History File window, but you can see the RPM Value where you cursor is at in the Trace Box. Look at the top of the window for the time value, then the Trace box for the RPM value. Tip: Use your right and left arrow key to move forward and backward one step at at time.

If you don't mind getting your hands dirty, data wise that is, you can get what you're wanting by importing the data into a spreadsheet.

The .acq files are just text files, open one in a text editor, copy the *Data* section out - In the *Name* section are the row headers you'll need. You can stick that info in a spreadsheet and work with it whichever way you want. The Box records an entry every .01 seconds, just add a column "TIME" with .01 for each entry.

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Re: MSD 7531 graphs

#8 Post by BigDog67 » Mon Jul 12, 2010 9:40 am

John_Heard wrote:
BigDog67 wrote:Excellent!!!! Now for the second question, how can i do this but have it so i can move my cursor over it to compare RPM and time? Like on the Revlaunch graph.

On the "history file" is shows the X plane in time and the Y plane in a %. How can i get this so the Y plane shows RPM so i can figure out what my converter is doing.
MSD Doesn't let you change the X/Y Values in the History File window, but you can see the RPM Value where you cursor is at in the Trace Box. Look at the top of the window for the time value, then the Trace box for the RPM value. Tip: Use your right and left arrow key to move forward and backward one step at at time.

If you don't mind getting your hands dirty, data wise that is, you can get what you're wanting by importing the data into a spreadsheet.

The .acq files are just text files, open one in a text editor, copy the *Data* section out - In the *Name* section are the row headers you'll need. You can stick that info in a spreadsheet and work with it whichever way you want. The Box records an entry every .01 seconds, just add a column "TIME" with .01 for each entry.

I did not even look at the trace analyst box as i was moving the cursor, I see the rpm changing now. I was trying to open my .act file in notpad or microsoft word and all i get TONS of lines of numbers with comas ect? I do not have a drive shaft sensor but the car is going into a wheel stand so i know it its hooking but the first gear goes to 7,000 rpm in .86 seconds?.. I get a 1500 rpm drop from the 2nd to 3rd gear change. Did i roll a sprag in the trans or converter?

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Re: MSD 7531 graphs

#9 Post by John_Heard » Mon Jul 12, 2010 10:15 am

Sure it can go launch RPM to 7000 in .86 seconds, just depends on the stall speed of the converter, power etc.

The converter should start to pull down the motor as it approaches it's stall speed. For example mine goes from 3400 to 5000 in .33 seconds, then you can see the converter start to load it down as it approaches stall speed. A looser converter would let it flash faster and higher.

1500 drop from 2-3 isn't way out of line, it does mean your converter is somewhat tight but not necessarily a problem depending on if the car likes it or not.

You'll want to use a real text editor to manually edit and work with the .acq files, like http://www.textpad.com/, Notepad and Word suck for that. Sorry, I don't really have the time to go into how to make Comma Delimited text files and all that. The data is there to work with if you want, but you'll have to screw around with getting it imported into Excel. It would take me quite a while to explain the process.

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Re: MSD 7531 graphs

#10 Post by BigDog67 » Tue Jul 13, 2010 7:17 am

http://i886.photobucket.com/albums/ac67 ... stgear.jpg

I lifted due to the car drifitng twards the wall in the wheel stand. I do not see the converter flashing unless the slight arch in the middle is it?

John can you post a run of yours so i can compare, my setup is new and i am trying to work the kinks out.

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Re: MSD 7531 graphs

#11 Post by John_Heard » Tue Jul 13, 2010 8:53 am

The slight arch is probably it, if you stretch the graph out/zoom in it will be more pronounced.

Here's one of mine, a bit too much tire speed but it'll give an indea.
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trace.jpg

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Re: MSD 7531 graphs

#12 Post by John_Heard » Tue Jul 13, 2010 8:54 am

It's really helpful if you have a data logger to compared the diff between what the engine is doing vs the tire.

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Re: MSD 7531 graphs

#13 Post by BigDog67 » Tue Jul 13, 2010 7:01 pm

John_Heard wrote:It's really helpful if you have a data logger to compared the diff between what the engine is doing vs the tire.
Yes, i called RPM guys and they can get me what i need for $850. I will be looking into geting one soon.

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