Help adjusting speed in 747 truck bin file?
#1
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Car: 67 Firebird Convertible
Engine: LB9
Transmission: 700R4
Axle/Gears: 3.55
Help adjusting speed in 747 truck bin file?
I'm trying to help a friend get his speedo calibrated on his 89 Chevy pickup.
Some one before him put 29" tires on the truck and the speedo is too slow.
The trans has the magnetic pickup, so the gears can't be changed.
I would assume that there would be a place in the bin file for the 747 to make a change.
Any help would be appreciated. I searched and found lots of answers to change gears in trans, but this is a magnetic one.
Thanks,
Ron
Some one before him put 29" tires on the truck and the speedo is too slow.
The trans has the magnetic pickup, so the gears can't be changed.
I would assume that there would be a place in the bin file for the 747 to make a change.
Any help would be appreciated. I searched and found lots of answers to change gears in trans, but this is a magnetic one.
Thanks,
Ron
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maybe I can help you here. I put a 5 speed manual trans from an 89 or 90 pickup and know the magentic pickup you have. I don't believe the 747 ECM allows the changes you want to make. (but if you find a way to do it, please let me know!!)
But there is a module in the dash that allows for recalibrating the speedo. I had to use that part of the dash to make the ECM see the right speed in my 85 truck. I was able to research the module and it basically came down to cutting or jumpering pins on the circuit board. SOmewhere I have this, if you can't find it (try GOOGLE) and I can go through my stuff. Good luck.
But there is a module in the dash that allows for recalibrating the speedo. I had to use that part of the dash to make the ECM see the right speed in my 85 truck. I was able to research the module and it basically came down to cutting or jumpering pins on the circuit board. SOmewhere I have this, if you can't find it (try GOOGLE) and I can go through my stuff. Good luck.
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The 7747 does not support changes to the speedo. That's all handled thru the VSS and gears.
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Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
I think Greg is referring to the DRAC module modifications to get different outputs.
Do a search on "speedo-calibration" and or DRAC modules
Stupid link won't work even though I pasted it directly.
Might have what you're looking for.
Do a search on "speedo-calibration" and or DRAC modules
Stupid link won't work even though I pasted it directly.
Might have what you're looking for.
Last edited by JP86SS; 09-21-2006 at 04:54 PM.
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Car: 67 Firebird Convertible
Engine: LB9
Transmission: 700R4
Axle/Gears: 3.55
I should have know that it is the same basic thing as the 3rd gen stuff, duh. I'll try to find it tomorrow.
Thanks a million guys for the help again.
Ron
Thanks a million guys for the help again.
Ron
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Car: El camino 70 ss
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