AUDI A4 1998 B5 / 1.G 01A Transmission Calculations Workshop Manual
Page 1 of 2
00-12
Calculations
Ratio i, calculating
Transmission ratio
Transmission
ratio = No. of teeth
driven gear : No. of teeth
drive gear
Ratios
Formula
iG = gear ratio ZG2 : ZG1
iA = axle ratio ZA2 : ZA1
iov = overall ratio iG x iA
Example:
5th gear
Final drive
Drive gear ZG1 = 37 ZA1 = 9
Driven gear ZG2 = 31 ZA2 = 35
Calculations:
iG = 31 : 37 = 0.838
iA = 35 : 9 = 3.889
iov = (31 : 37) x (35 : 9) = 0.838 x 3.889 =
3.259
Pa
ge 1 of 2 Calculations
11/19/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.TM02.00.4
Page 2 of 2
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Vehicle speed V, calculating
V
=
n : iov x UA x 0.06
n = Engine speed (RPM)
iov = Overall ratio
UA = Dynamic rolling circumference of tires
(m)
V = Vehicle speed (km/h)
Example:
V = 1000 : 3.100 x 1.93 x 0.06 = 37 km/h
At an engine speed of 1000 RPM, the vehicle
road speed in 5th gear is 37 km/h.
Pa
ge 2 of 2 Calculations
11/19/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.TM02.00.4