I'm curious, why was Type 321 stainless steel selected for the flexible cross pipe? It is very similar to Type 316, except that it has added Ti, designed to stabilize the metal in high temperature service (<450C), and particularly during welding, so that the stainless steel retains its full corrosion resistance. It's mechanical properties are identical to Type 316 stainless steel.
Was Type 316 stainless steel used for the CAT bypass pipes as in your other exhaust designs?
The flexible cross pipe is made in SS 321 because the company that did for me utilize this material for that products, at the two extremity they welded two little pipes of 304L for fit with my pipes.
In my products i use generally the SS grade 304L, and the 316L only for the outer pipe of the tails, this for have better corrosion resistance on the time.
For the 599 i'm using the grade SS 409 OD 65x1.2 pipe, i used for the extension pipes on the CAT, for the CAT bypass pipes and for the back mufflers.
The choice for the SS 409 OD 65 x 1.2 pipe it was driven by different reasons, my bending company was equipped for this pipe dimension, I felt this diameter right for my project, and i found on a market only the 409, that is the material utilized by the original equipment of the sports cars, then i think that is ok.
However I had to purchased as minimum 1 "package" directly by the steelworks (Terninox SpA
), the package it was 237 m of pipe ....
Probably in the future if i wil need more pipes they can make me in the material i want .... perhaps