4-bolt to 5-bolt conversionQ

["Brandon Hull" <brandon@cardinalventures.com>]

>4-bolt to 5-bolt conversion

>catalogues, they sold metal discs that bolted onto your rotors and
>allowed you to use a different bolt pattern

Some of us have looked at this long and longingly.  I can give you at least
the benefit of some related research:

1)  The european S2 has a 5x112mm bolt pattern, and the hub of that car is
interchangeable with the US coupe quattro, which has the same pattern 4x108
as your 80Q.  Whether the US cq and 80 hubs are interchangeable, I don't
know.  The hubs are available from europe at about $80-100 each, plus you
need to replace each wheel bearing.  And brake rotors of course.  Everything
else lines up.

2)  If you take a compass and a piece of paper and trace a 4x108 pattern
over a 5x112 pattern, you'll see that it is impossible to avoid conflict
between holes.  I tried a variation on this, attempting to make an adaptor
from 4x108 to 5x130, the std porsche pattern, and while the holes don't
conflict literally, the stud heads would.  You also have the problem with
offset, although since the Cq, 80, 90 is 37mm, and most porsches are 52, you
get the benefit of a 15mm thick adapter ring which is probably adequate.

But then you ask yourself, adequate for what?  After all this work, you have
a solution that is weaker than what you started out with,  and you've
multiplied the number of possible fastner and component failures by some big
number.  I finally gave up, found a wheel that fit, and looked a lot like
the Porsche cup wheels I coveted, and have learned to be happy sharing the
same bolt patterns as 4 cyl mustangs and Neons.

HTH,

Brandon Hull
ersatz S2
http://www.20v.org/s2/