Highway mode without speedometer
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Highway mode without speedometer
how Would I go about enabling highway mode without a workin speedometer? The speedo gears are stripped out. Have a wb and ebl and right now on the highway it’s getting on the 14’s afr
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From: Mile High Country !!!
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Highway mode without speedometer
Last edited by Tuned Performance; Jan 17, 2019 at 12:38 AM.
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From: Chasing Electrons
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Transmission: check
Re: Highway mode without speedometer
There is another way, get whatever driven gear you can and install it. Then wire a Dakota Digital SGI-5 box between the VSS and whatever buffers he VSS (buffer box on TBI and MAF TPI, ECM on SD TPI).
The SGI-5 box is programmable so the incorrect VSS speed can be corrected.Then if you change tire size or rear gear ratio, can just reprogram the box.
RBob.
The SGI-5 box is programmable so the incorrect VSS speed can be corrected.Then if you change tire size or rear gear ratio, can just reprogram the box.
RBob.
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Re: Highway mode without speedometer
Not sure about your exact situation, but these guys may have something that would enable you to maintain an electronic speedo output...
https://jagsthatrun.com/collections/tpi-tbi
https://jagsthatrun.com/collections/tpi-tbi
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Re: Highway mode without speedometer
Thanks. My speedo works occasionally when the gears catch but they’re the wrong gears so I have the ecm set to read the right speed with the speedo off. I think I changed the ppm? Anyway, with the Dakota would I need to set the back to stock?
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Highway mode without speedometer
Yes, changed the PPM. To do the SGI-5 box correctly setting the PPM back to stock should be done. This way the dash speedometer will also be correct. The dash speedometer gets 4K PPM while the ECM gets 2K PPM. Note that this is for the EBL Flash, if using the EBL P4 then the ECM also uses 4K PPM.
A note about the chewed up speedometer gears. For the drive gear there are two locations on the output shaft for it. If the one for the Corvette is used the gears get ruined. So if the trans has ever been apart that should be checked.
RBob.
A note about the chewed up speedometer gears. For the drive gear there are two locations on the output shaft for it. If the one for the Corvette is used the gears get ruined. So if the trans has ever been apart that should be checked.
RBob.
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Re: Highway mode without speedometer
I see. I’m fairly sure it hasn’t been apart yet but it stopped working at 142k. I replaced the driven gear with the new original and it worked for a few days before stopping again :/ good info l, thanks
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Re: Highway mode without speedometer
How far off would it be if the driven gear was 1 tooth off? Edit: found the right gear finally. Guess they make them again?? Couldn’t find them a couple years ago
Last edited by Faolan; Jan 21, 2019 at 10:24 AM.
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