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TR6 New trans and speedometer
- Thread starter robatc
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CJD
Yoda
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If you are sure it's 20%, this adapter would be the easiest fix
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The speedometer drive runs off a worm gear at the transmission output. I know nothing of the Miata transmissions, but it seems that their worm gear may have a slightly different ratio. I'm surprised that the people who sell the conversion kit haven't done something about that.
Before doing anything to compensate, you need to know precisely what the difference is. That is best done with the odometer. Be sure your tire pressures are right, then see what your odometer indicates over a several mile stretch of road; mile markers on the freeway are perfect for this. Once you know the error exactly, you can shop for a correction gear such as the one John identified.
Before doing anything to compensate, you need to know precisely what the difference is. That is best done with the odometer. Be sure your tire pressures are right, then see what your odometer indicates over a several mile stretch of road; mile markers on the freeway are perfect for this. Once you know the error exactly, you can shop for a correction gear such as the one John identified.
tr6nitjulius
Jedi Warrior
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For a visual calibration of mph my TR6 side by side on fwy for several miles with G.F. in her 2007 Saturn Sky via walkie talkie told her to cruise control it @70 mph TR6 4-5 mph lower. Speedo refurbed new cable, 205/70/15 tires
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The Miata used a 4;11 final drive(on most years) The 3;70 in your car is causing the variance.
I would suggest it is actually close enough if only 5mph slower. Has it hit you that the 17 year old Pontiac
might be off a tad?? Use a GPS speedometer to get a real reading. I bet it is 10+
Mad dog
I would suggest it is actually close enough if only 5mph slower. Has it hit you that the 17 year old Pontiac
might be off a tad?? Use a GPS speedometer to get a real reading. I bet it is 10+
Mad dog
mastaphixa
Jedi Trainee
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A great phone app called speed box would help. My speedo is about 10 mph off at speeds above 20 so I just have my phone set up with speed box so I can get an accurate display of my speed.