This article is from the VW Performance FAQ, by with numerous contributions by Jan Vandenbrande others.
A:The following tires sizes (see the r.a FAQ for how to
read these) result in equivalent circumferences and
standard on most passenger VWs over the years. The
implication of this list is that in principle (if you
have clearance!) you could upgrade your tire/rims by
traversing this list! The whole aim with changing to
different tire sizes is to stay within a reasonable
margin of the original tire diameter.
155/80-13 => Rabbit (1975-1978), Golf Diesel, maybe other
A2's
165/70-13 => Rabbit (1979-1984)
185/60/14 => Scirocco, Jetta, Rabbit GTI [with "Snowflake Alloys"],
optional for Rabbit, most non- performance A2s, A3 Golf
185/55-15 => GTX (16V Jettas in Canada), 16V GLI
185/60-14 => Golf GTI, Jetta GLI (85-87) Carat (86-89),
Jetta (90-93), Scirocco 16V, A3 Golf
195/60-14 => Quantum, Passat, A3 Golf
205/55-14 => Golf GTI 16V (1987-1989)
195/50-15 => Golf GTI 16V (1990-), Jetta GLI/GTX 16V, Passat
GL (1991-)
195/50-15 => Corrado G60 (1991-1992)
205/50-15 => Passat Syncros G60 (1991 +), Canadian 1991
Passat GL
205/50-15 => All VR6 models; 5-bolt rim
215/50-15 => All Passat VR6 models; 5-bolt rim; 6" rim
Some non-factory combinations are:
205/60-13
215/45-15
 
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