ALUSIL ® -Cylinder Blocks Porsche V6/V8 - KSPG AG

Whereas in the standard FSI engines the cooling water flows
around the cylinders from the front to the rear, in the case of
the V10 bi-turbo a cross-flow principle has been implemented.
Thanks to forced flow, the cooling effect is enhanced in
both the cylinder block and the cylinder head.
The oil circuit ducts are partly pre-cast, partly drilled. The
two deep-hole bores centrally arranged in the V, for the main
oil and injection nozzle channels for piston cooling, which
virtually cover the whole block length, are machined at KS
Aluminium-Technologie. The non-pressurized oil drain backs
and cylinder block vent ducts are pre-cast for the V8 and V10
cylinder blocks. They are arranged externally on the side
walls, in parallel with the cylinders. These channels are connected
with the bedplate through bores in order to exclude
the risk of casting fins being left.
Subsequently, after removing the sand cores, the cylinder
blocks are submitted to first cut machining (Fig. 11).
Adjustment in the crankcase area is achieved by alignment
in the first clamping step, starting from cast locating points
at the interface to the bedplate. To this effect, the three locating
points on the gearbox side are machined and two index
bores (fitting bores) are set.
8
Fig. 9a : The Audi V6 gasoline engine
Further machining steps in the first and second clamping operations
are the drilling of the oil ducts, pre-drilling of the
cylinders, pre-milling of the main bearing area and cubing of
the external faces. In this last step, all “important” surfaces
are re-milled in order to remove casting fins, for instance, in
order to enable a process-reliable leak test to be carried out
subsequently.
To ensure proper casting quality, the cylinder blocks are
submitted to comprehensive x-ray, hardness and ultrasonic
tests. The latter serves to check the bearing bulkheads for
porosity. The oil and water systems are checked for leaks by
means of a differential pressure test, followed by a 100% visual
inspection before the cylinder blocks are dispatched to
Audi on purpose-designed loading devices.
At AUDI HUNGARIA MOTOR Kft. (AHM), the cylinder blocks
are integrated into the machining line on the locating points
and aligned on gearbox flange level by means of the fitting
bores provided in the gearbox flange. Next, the cylinder
block is machined as an individual part, with most of the
machining work being done in these working steps. Subsequently,
the finished bedplate is “matched” with the cylinder
block, i.e. pinned and bolted. From this moment, the cylinder