Dallas Mustang Speedcal

[Un4GivN]

I've had a DM Speedcal on my car for 2 years now, never had any issues. However, I put my built rear in today with 4.56's, changed my speedcal settings, started it up and took off... About a tenth of a mile into the trip at about 25mph in 3rd gear I look down and notice my speedo is wrapped around to 120. I have checked and rechecked my settings I don't know how many times.

I'm sure most of you will say to ditch the speedcal and change it with my tuner, but I don't want to unless that's my last resort. I could really use some input here.

 

[trxcobra]

i hated that speedcal and ditched it for a tuner. good luck!

 

[03SVTSnakeBite]

Tuner FTW

 

[Gallows]

See Mark Olson's Mustang Cobra or here Recalibrator & Speedcal Calculator Hope the links help.

 

[Predatorbird]

Grab video camera, take video of how fast your car goes from 0-120, post on youtube. :-D

After that, remove speedcal and get the car tuned.

 

[Janstang]

Do you still have the manual that came with the speedcal? It should get you close or steer you in the correct direction to setting it up close.

 

[Un4GivN]

My car is tuned and I could change the calibration with my Xcal... However, I would have to remove the speedcal and wire everything back up stock. Some of the wires are too short to reconnect and I will probably have to rewire the connector pins. This is why I want to make the speedcal work.

I do not have the manual that came with the speedcal because I bought it used, but they do list all of the directions on their website. I've been through them and through them and cannot find any faults. I have the correct settings for the 4.56's. I did not have any issues until I changed these settings.

 

[Janstang]

If I was you I'd grab a GPS with MPH readout and go out and check it at 65mph. See how far off it is and make adjustments based off their directions. If you can't get it to correct, then its time to dump it and do the SCT adjustments based off gearing, tire size etc..

 

[PSUCOBRA96]

I have heard you have to see how far you are off and then call them for the adjustment, the directions are not always right or something I heard

 

[SVR-S]

I was told to hook up GPS,set mileage to zero,set speedo trip to zero,drive for 10 miles exact showing on the gps,record mileage on the speedo trip and then phone DMS.Guy will then give you the correct code.Worked for me.

 

[cobrasvtcoupe25]

Sorry I can't really help with your post Perry, but how do you like the 4.56's?

 

[Un4GivN]

Well... I finally said screw it. DMS is in the trashcan, everything is wired back up and working correctly.

Sorry I can't really help with your post Perry, but how do you like the 4.56's?

Only had it out for one heat cycle and I'm gonna put a couple hundred miles on it before I give it hell, but so far I can't tell much of a difference.