Steel vs. Titanium
The steel at the headline is of course stainless steel. But not only the expensive tubes of tuners, also the standard tubes are now almost all made of this material. Connections can be made by welding or detachably by
pushing them into each other and fixing them with pipe clamps. The latter requires expansion by means of an expanding mandrel and the slitting of one of the pipes to be connected.
Pipe bending is a special challenge. Of course, the cross-section must not become oval at such points. In principle, it must be retained in this way. It would be possible to have two straight pieces or rolls on the outside and
one inside, which would fit the pipe halfway. Then there is also the bending mandrel, e.g. as a coil spring for simple bending work to fit the inner contour. Steel pipes require material with a larger cross-section that has
already been coiled.
We come to Akrapovic, where stainless steel equipment is also manufactured. But the company has a worldwide reputation for processing titanium. It cannot be said in principle that titanium allows the exhaust gas to flow
through the system more quickly, but it certainly represents an enormous weight saving, especially since Akrapovic also manufactures the pipes for this itself.
Akrapovic originally comes from the racing sector. They are still used to modifying even during a racing season in order to get the best possible performance. Here, of course, the additional weight advantage is particularly
important, not necessarily resulting from the density, but rather from the particularly filigree construction.
The wax model of a small piece of Y-branch pipe with a wall thickness of far less than one millimeter, which is made by a 3D printer, is coated with ceramic until this mold is stable enough for a casting process under a
certain pressure. Several such ceramics in a circle then rotate in the furnace while being supplied with titanium from the centre.
This Y-branch pipe is then wafer-thin, without a weld seam or other disturbances of the flow, not to mention its possible additional weight. The parts of the outer skin made of carbon serve the same purpose. All in all, not
only the workmanship shines, but also the function.
Unbelievable are the small tolerances of up to a hundredth of a millimeter, which are only allowed here. Extensive test track with performance test stands for motorcycles as well as for sports cars. State prescribed tests can
be carried out here on site, which of course increases the seriousness in a market area that is not always completely clean.