Join Date: Jan 2009
Thanked 3 Times in 3 Posts
no offense dude but I dont know where you got your information on 409SS for exhaust systems but you are misinformed. 409SS will rust. 90% of the cars being manufactured have 409SS exhaust. Some Honda and toyotas are using 441 and 440SS. 304SS is used in some higher temp applications or tight bend radius's. Now if your talking about taking an ehxaust system and setting it outsided and seeing if it will rust....thats a completely different story. Considering your not subjecting the material to any heat cycles or heat cycles with corrosion it will last a very long time. Granted AL409 will rust about 40% quicker then 409SS. I can show several studies done by AK steel (largest tube supplier for exhaust for OE's) showing the corrosion rates and deteriation due to temperatures and the elements. The hotter the exhaust gets the quicker it will rust and deteriate. 409SS in a 1.5mm thickness will not last that long at 1400F+ temps. For gas applications 1400F is fairly low. For older diesel technology...i.e dpf less exhaust systems would never get over 1000F. These new DPF exhausts will get up 2000F. BTW the 6.4L stock exhaust is a combination of 439SS 304SS, and 409SS. FYI I design DPF's DOC's converters for a living.
06 F250 6.0L ID tuning. RCD EGR delete 03 turbo