new in 7531 box

MSD Digital Ignition Programming & Troubleshooting, Playing with Dots, Slew and other fun toys for traction challanged racers

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mopar540
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new in 7531 box

#1 Post by mopar540 » Tue Nov 10, 2009 5:21 pm

hy im changing my 7al-3 box for a new 7531 box thinking in have more control in the launch off the car and more top end speed but the real deal with changing the ignition module its because i think i can launch harder with the launch retard and better respnse with the gear retard

we have an awfull track as you seen on the videos i post in my last add im changing tires for a set off 33x10.5x15 instead off the 31x10.5x15 thinking in get a little larger the last gear

i hope get some help with the initial programing off my box because im new on this kind off programings any advice are welcome

thanks a lot

alberto
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vegaracer
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Re: new in 7531 box

#2 Post by vegaracer » Tue Nov 10, 2009 6:00 pm

There are a few of us on here running them, so we should be able to answer your questions.
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mopar540
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Re: new in 7531 box

#3 Post by mopar540 » Tue Nov 10, 2009 10:36 pm

ok here aremy first questions jajajaja

i have a 500ci mopar engine in a 2900 pound car and i cant go off the line with out burn the tires all the way down the track i was thinking if i get the launcho retard like 10 degrees down i can get the trans brake higher and have a bit more tracion off the line , am i corrrect to get fron 38 degrees to 28 with the launch retard?

and the other one is how much can i gain if i retard the timing 5 degrees in 3rth gear can i gain more top speed or what ?

im getting this msd because im fighting for the national championship here in peru (southamerica) thats what im triying to do things whrite i will appreciate a little help and explanation off how to program this msd box

thanks a lot for your time

alberto
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Re: new in 7531 box

#4 Post by John_Heard » Wed Nov 11, 2009 7:16 am

Yes, you can use the Launch Retard feature to yank out 10 degrees and ramp it back in as quick or slow as you want.

Keep in mind that the launch retard also takes out the same amount of timing while you're on the transbrake (it's active at that point as well). The timer starts counting down in it at the moment you release the transbrake.

Hard to say about the high gear retard if you'll see a gain there or not. It's easy to do using the gear retard feature in the box.

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Re: new in 7531 box

#5 Post by mopar540 » Wed Nov 11, 2009 7:34 am

thanks for the replays ill be testing the car this weekend and try to make it work with the basics off programing to keep the car running hard and not blew something

cani set an a rpm limiter by each gear, and theres another thing that i dont understand to much is the slew control how this work exactly and its necesary

thanks
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Re: new in 7531 box

#6 Post by John_Heard » Wed Nov 11, 2009 7:49 am

The RPM Limiter Curve (DOTS) doesn't have gear selection. Wish that it did, it would make it a lot easier to work with if you could have separate curves for each gear. I wouldn't advise playing with the curve (Dots) until you have at least one good solid run recorded in the History File in the box. Make sure and save those after every pass!

You can take that history file RPM curve and copy it over to the RPM limiter Curve setup to set it up.

Most people are not using the slew feature, they use the RPM Limit Curve/Dots. Those that do only use Slew use it in high gear where the RPM per second rates are more linear.

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Re: new in 7531 box

#7 Post by mopar540 » Fri Nov 13, 2009 7:53 am

hi i just make a few programs on my msd but im not to sure if im making the right thing i just want to nkow f some one have like a universal setup can share or maybe help me program my msd because i fell the car goes wrong my best et yesterday in the track was 10.54 :pissed: i dont nkow waht happend jajajjaa

im new in this kind off programing appreciatte any help thanks a lot

alberto
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Re: new in 7531 box

#8 Post by John_Heard » Fri Nov 13, 2009 8:22 am

I don't know of any universal setups. There's too many differences between cars I think for most setups to be able to do that?

You ran the car with the 7531 box and it didn't run as good as before? Did you save the launch history (.acq) file from each of your passes?

We can try to help you here with it, there's a number of people that use the same box.

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Re: new in 7531 box

#9 Post by mopar540 » Fri Nov 13, 2009 1:20 pm

i open to se the history off ecah run and i can see it yesterday but i try to see it nkow and its gone maybe i do something wrong mmmmm but im going to try with the sam esetup today with the the retard in 3 gear and taking 10 degreees off on the launch and see what happend

but lets say whats the way to get a concistent setup? you think im running to high advance im running on 39 degrees and taking out ao degrres on 3rd gear ?

thanks again

alberto :thumb:
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Re: new in 7531 box

#10 Post by John_Heard » Fri Nov 13, 2009 2:25 pm

mopar540 wrote:i open to se the history off ecah run and i can see it yesterday but i try to see it nkow and its gone maybe i do something wrong mmmmm but im going to try with the sam esetup today with the the retard in 3 gear and taking 10 degreees off on the launch and see what happend

but lets say whats the way to get a concistent setup? you think im running to high advance im running on 39 degrees and taking out ao degrres on 3rd gear ?

thanks again

alberto :thumb:
When you connect your laptop to the MSD box it will download the last run's launch history. In the launch history window, click file and save as. I'd recommend using a file name that has a date, like 111309-run1.acq - that way it makes it easy to find which one you want later. Then once you've saved it to your computer you can reopen it later in the launch history window.

It's hard for me or others to guess at what your car needs for the setup on the box, like the launch retard or a gear retard without knowing what the car is actually doing. I assuming the car spins at launch more than you want that's why you're asking about the launch retard. Yeah, that should kill some power if you use it. I'm not sure if you need 10 degrees or not, or how long you need to set it up for, that's something you'll have to play around with.

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Re: new in 7531 box

#11 Post by mopar540 » Sat Nov 14, 2009 12:55 am

i make the last run off the night with just a few changes in the msd and went 10.00 the best et off the night i just realise that the installer off the msd let the yellow cable from the shift ligh unplug and i dont nkow how to conected because i dont understan how to conect it can you helpo me on that ?

thanks
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Re: new in 7531 box

#12 Post by John_Heard » Sat Nov 14, 2009 6:16 am

The Yellow wire that is in the big plug on the MSD box is the shift light wire. When the shift light activates, that wire will ground up to 3 amps of current.

So on the light itself, you'll need 12 volt Positive going to it, then the ground wire from the light goes to the MSD Yellow wire.

Good to hear you made a better pass!

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Re: new in 7531 box

#13 Post by mopar540 » Sun Nov 15, 2009 8:18 pm

hi i just came off the racetrack today and not going so well because i have a rpm issue maybe i mesup some comand on the msd but it was like the car takes off the line ans wen he gets to 5500rpm starts to drop the rpms and suddenly goes up and that happend all the way down the track in ech gear and i dont think what happend or what i move because i load the same setup as i made 10 flats the other night any way i have a lot to learn off the msd programable and i appreciatte all replays and tips to improve my nkowwlede on the msd digital world jajajaja

thanks

alberto :thumb:
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Re: new in 7531 box

#14 Post by John_Heard » Mon Nov 16, 2009 6:41 am

Sounds like you may be having a fuel issue if it's laying over then picking back up. Might want to check float levels, fuel filter, etc.

You sure do get a lot of passes in during the week, where do you race at?

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Re: new in 7531 box

#15 Post by mopar540 » Mon Nov 16, 2009 8:31 am

i live in SOUTH AMERICA,PERU and we do not have a certified track till next year so we have to rent ands old light planes airport so we can race over there and tests the cars and we have only 5 or maybe 6 races a year for the champinship over here thats why we have to rent the track 3 days before to tune our cars and try to get them to the very best tune up

i reralize that in the last pass i see the fuel pressure gauge and was going between 7-9psi im running normally on 8psi i have the pro star 500 fuel pump, and i have to quit because off a blown head gaskett

im going to put thge exact parameters in my setup and maybe can realise if something its wrong

thanks :thumb:
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