Decided to pull this job on my M5 a couple days ago and documented it as much as I could. This job requires a couple of special tools which I will list and other things that need to be done prior to doing this job in order to do it correctly.
E34 M5 Throttle body balancing, adjustment and synchronization.
PRIOR to adjustment:
All 24 valves must be adjusted to spec (0.28 to 0.33mm
All ignition components in full working order ( Cap and rotor, coil, spark plugs, wires and crank position sensor)
All vacuum lines under the Intake Plenum must be fresh, can't have vacuum leaks.
All vacuum related rubber o-rings must be replaced.
Carbtune tool http://www.carbtune.com/
Brass screw o-rings 17211742635 x6
Throttle body to plenum o-rings 11611305124 x6
Vacuum hose, 1-2 meters of it.
Remove the intake plenum and replace every vacuum line in your sight
Remove the TB shocks using an 8mm socket or wrench
This is what they look like
Adjust the shock according to BMW specs
Use a vernier calliper to adjust to 98mm
Clean up the little shocks, use a drill with a wire brush bit, treat with oil after cleaning them.
Next step is to adjust the ITB throttle valves
Adjust by BMW spec (top 21.7mm, bottom 22.7mm)
Assemble everything back, use new o-rings between the ITBs and and Intake plenum tubbing (sorry forgot to take pics of that) O-rings p/n#: 11611305124. Assemble all the ITB components back.