question about TACH and Speedo
10-31-2012, 11:27 PM
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question about TACH and Speedo
Ok so I replaced my rear differential froma stock 2.42 over to a posi 3.23. In doing so I replaced my DRAC module with the DRAC out of the car I go the differential out of. this should have put my speedo dead on. (Its not!!) and ever since I have gotten the car the TACH reads about 200-300rpms higher than what the scanner says it is actually doing. Does anyone know what would cause this?
BTW, I have a 91 Z28 with 700r4. So speedo is electronically controlled by ecm and DRAC...no gears to change to alter.
BTW, I have a 91 Z28 with 700r4. So speedo is electronically controlled by ecm and DRAC...no gears to change to alter.
11-01-2012, 01:39 AM
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Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
11-01-2012, 01:43 AM
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Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
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