Gus

To answer the question on the larger vacuum reservoir - Yes - you will need to add the larger reservoir. The stock 964 vacuum reservoir is not large enough to operate the resonance flaps. You need the reservoir that goes in front of the left side rear wheel and looks like a lot of ***** black tennis ***** glues together .
I think I have the part number around here some place - will look for it - Bill's info is very useful

bassam

the previous owner had that vacuum reservoir installed on the driver's side of the engine, it's a bigger one with several tennis ball size spheres. The dme and wiring harness were supplied from instant-g company (have extra plugs and wires to connect to older 911) and has a cyntex chip that says (hand writing) 993 vario. I connected all the wiring to engine and looks like it's a plug and play on the engine side. need to remove driver's seat and hope it will be the same with the plugs there ( my car has short gears 6 speed transmission and dont think I will gain anything on the track with the varioram, will consider switching to 993 plastic manifold and rennsport chip. Thank's again for replies and will keep you posted as will start working on the car after all turkey leftovers are gone.