people with APR chip and 18in wheels what does your speedometer say
11-16-2001, 08:12 AM
#2
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changing your wheel size doesn't affect the read out mph/rpm ratio
You could remove the wheels from your car, put it up on blocks, run it, and the speedo will still read the same thing at the same rpm ranges.
11-16-2001, 10:00 AM
#4
Wrong.,...
it will change the speedo reading if you put incorrect wheel/tire sizing. The car is calibrated to have certain size diameter wheel/tire mix. If you below or over that size, it will affect your speedo, but it will not affect your engine speed.
11-16-2001, 10:24 AM
#5
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Wrong.....
Let's say:
With stock tire wheel/tire:
80mph @ 4000 rpm on speedo/tach
Actual mph = 80 mph
with aftermarket wheel/tire (let's say 5% smaller):
80mph @ 4000 rpm on speedo/tach
Actual mph = 84 mph
The speedo driven gear is in the trans, and since the overall gear change is at the tires, the speedo sensor does not pick it up.
With stock tire wheel/tire:
80mph @ 4000 rpm on speedo/tach
Actual mph = 80 mph
with aftermarket wheel/tire (let's say 5% smaller):
80mph @ 4000 rpm on speedo/tach
Actual mph = 84 mph
The speedo driven gear is in the trans, and since the overall gear change is at the tires, the speedo sensor does not pick it up.
11-16-2001, 10:42 AM
#6
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Well I confirmed it another way I used the code in the climate control to monitor
real time speed in Km found out my speedometer is accurate the only thing that king of bothers me stll is off throttle the needle tend to drift down to zero slowly.
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11-16-2001, 02:28 PM
#10
I think you mean 5% larger. My SUV wheels are over 10% larger in perimeter so I always have to
drive at 62mph to do 70mph relative to mother earth 
did you get the links? install? any problem? email me. Thx.
did you get the links? install? any problem? email me. Thx.