Originally Posted by Z28ricer

Using mandrels for bending tube: Type and placement are critical for successful bending

Mandrels typically are made from an aluminum-bronze alloy or a tool steel with hard chrome plating. An aluminum-bronze combination is used to bend stainless steel, titanium, INCONEL®, and other hard materials. Chromed tool steel mandrels shouldn't be used to bend stainless steel, but are useful for most other hard materials and also for mild steel, steel, copper, aluminum, and other soft materials. There are also some situations in which chromed tool steel mandrels can be used with more success than aluminum-bronze for bending titanium and INCONEL.

Titanium can be mandrel bent, ready cut mandrel bends like stainless, mild, and aluminum just arent that easy to find, either way, a pie section can be very handy when fabricating something, not many were used in the manifold itself, but as you can see, can be helpful even when building an eleventy billion dollar exhaust.

Originally Posted by LongFellow

The manifold is titanium, hence the pie cuts.