I'm doing a brake job on my 1988 928S4 and I'm replacing the rotors with Zimmermans. When look at the left hand front Zimmerman compared to what is currently on the passenger side, the vein direction is the opposite. I'm under the understanding the in Europe; right=driver's side and left=passenger side. If that is the case, the current rotors are installed wrong.
How can I verify that I'm installing on the correct side?

 

Dimmer,
Look at the rotors, they are basically a squirrel cage fan. Imagine the car driving forward and picture which way the rotor will turn. The air travels from the center of the rotor out.

This should help you figure it out.

 

Ok ... that helps. If I basically think of it as a centrifugal air pump, then the current rotor is installed correct. Makes sense. The whole right/left vs. Europe/NA thing had me confused.

Thanks again for the very quick response! This forum is awesome!

 

it should be pretty straight forward to think of it that way. just think of the vains pointing backward, or to the rear, when viewed from the top as they plung to the center hub.

 

That was short answer. Long one is in below link.

https://rennlist.com/forums/928-foru...each-side.html

Even shorter answer is, left = drivers side on LHD car.

 

If you place a pencil into the outer edge of the rotor, it should point to the rear of the car

 

not on the bottom of the rotor.

 

When looking from the top of the car.... place a pencil into...

Edit :Mark you must be acustomed to be using a lift

 

Or maybe Mark uses some anti gravity **** that we all need to know about; as putting the pencil in one of the openings on the bottom of the rotor the pencil will not point either way because it will FALL OUT! LOL!

 

Jeapers, doesn't anyone have the page from the WSM to post for this?

If anyone can tell me the volume / page I'll scan it quick...

 

Perhaps a pic will clear the point: