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Speedo problems...need help please.

662 views 2 replies 3 participants last post by  scorpiocgg 
#1 ·
My stock rearend broke, so I replaced it with an 04 Mach 1 rearend. I know the gearing is different than what used to be in there and my options are basically to either buy an electronic speed recalibrator, or use a reprogrammer to modify my ECU. Rather than pop $100 for the recal box, one of my friends has a Diablo Predator Tuner so I used that. It is the right model number for my car, and I reset it before using it so I tuned my car with the stock tune.

No matter what gearing I enter into it, my speedo just won't go back to normal; it either says I'm going to fast or too slow. I even tried changing the tire diameter according to the formula on Diablo's website and still nothing.

BTW, I have a manual tranny (T-5) and I believe my gears were 3.08 stock and now are 3.27's.

Can someone help me out please? Thanks...:)
 
#2 ·
Actually, depending on year, your stock rear was either a 2.73 (94-98 3.8) or 3.27 (99-04 3.8). All mach 1s have a 3.55 ratio.

Hope that helps
 
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