how off is it?
05-23-2006, 12:33 AM
#11
5th Gear Member
Join Date: Jan 2006
Location:
Posts: 4,053
RE: how off is it?
ORIGINAL: g2_5point0
I have a 1990, and from what i see on the tech articles, i'd only be able to calibrate 3.55's to a correct reading. What if i installed 3.73's, will it always be off?
I have a 1990, and from what i see on the tech articles, i'd only be able to calibrate 3.55's to a correct reading. What if i installed 3.73's, will it always be off?
05-23-2006, 12:45 AM
#12
2nd Gear Member
Join Date: Sep 2004
Posts: 394
RE: how off is it?
Yes, if you can't find the right speedo gear, it will always be off. To see how much its off take the speed reading on your speedometer (or miles on your odometer) and multiply by the gear ratio it's calibrated to and divide by the gear ratio that's actually installed on the car.
For instance;
100 mph reading x 3.55 calibrated ratio รท 3.73 installed gear ratio = 95.2 MPH actual speed
Likewise for 100 miles on the odometer you would have actually traveled 95.2 miles.
Of course this is all assuming that you have the same size tire OD that the speedo was calibrated for.
For instance;
100 mph reading x 3.55 calibrated ratio รท 3.73 installed gear ratio = 95.2 MPH actual speed
Likewise for 100 miles on the odometer you would have actually traveled 95.2 miles.
Of course this is all assuming that you have the same size tire OD that the speedo was calibrated for.