Minh, here you go
I added to the spreadsheet 2 tables where you can see the differences in km/h and %
The % is always the same, no matter how fast you drive, but of course the absolute difference in km/h varies and is relative to the speed.
Note that some angular gear ratio's are NLA. Usually, if the sites https://www.carparts-pros.com/page_1_3.php
give a price, it's available.
How much error is reasonable, depends on your personal preferences. For me, I'm happy it's would be < 3%. To calculate fuel mileage, it's easy to account for the error. I wanted it more precise when I follow tracks from roadbooks that indicate directions after a certain number of km "turn right at km 34, ..., ...", and it's more convenient to respect speeding limits
Rename this file to xlsx before opening (great trick btw, thanks!)
If the difference is negative (installed angular gear lower than the necessary gear), then the speedo reads lower than reality. My current angular gear is 0,421 and the speedo/odometer read 27% % lower than reality.
Make sur you understand the calculation, I wouldn't want that you order a wrong one. I can give you feedback in a good week or so, when I'll hopefully install the new angular gear.
Btw, I got a used #4: 0,476 and a #1: 0,421 which I plan to sell after re-sealing them