tipomac

Does anybody know the exact valve sizes for the US issued 1999 Audi A8 4.2 ABZ engine?

I am mostly interested about the length and the valve stem diameters as there are some differences everywhere I checked. I would like to order a set exhaust valve from Europe and their sizes for the stem diameter is 7mm. However Bentley repair manual says the it is 6mm for the US version. In Germany it is 7mm but for the 3.7 liter engine it is 6mm for both the exhaust and the intake valve as well. Is it at all possible to use 7mm stem diameter sized exhaust valves in the US 4.2 liter ABZ version? I am confused about this. I called up an Audi dealer and even they did not now or didn’t want to tell me.

Maybe if some of you people have an ETKA would be able to look into this. Anybody?

silverd2

All USA ABZ engines use the same valves 077109611D (exhaust) and 077109601K (intake) which should be 6mm. But earlier Euro ABZ's used 7mm (077109611C & 077109601J), but changed somewhere mid-model. The cylinder heads with 7mm valves have different part #'s than 6mm heads...would think you might need at least the proper matching valve guides.

tipomac

Thank you for clarifying this to me!