$189 EBay Cat Back - Eh? Not too bad actually.

[celek]

Originally Posted by stevo585

304 is 304. I use it pretty much daily at work. The difference in quality is usually the lack of passivation or other secondary treatments. It will last just fine. Like any brand name you pay for the brand not always quality. Especially on something simple like a exhaust that really cant fail badly. Now on a turbo or engine part yeah you want that to be a brand name with their reputation behind it.

Nike vs Sketcher is an example. Are Nike's better sure, but 4 times the price better? Not really.

Your statement is incorrect 304 is 304.
In order to be considered 304 the mixture in the metal has to be defined as below. The problem with Chinese 304 cheap stainless is they go minimum % of Chromium (Cr) and Nickle (Ni). and Maximum of cheaper materials like Iron (Fe) and Carbon (C)

This is why the Metal is cheaper and less of a quality, Although it fall within the constraints of 304 stainless it is a less quality material. Too much Carbon and the steel is brittle, too much Iron and it oxidizes faster. Not enough Chromium and Nickle causes rust spots. They also go extremely thin on the sidewall of the exhaust for minimal material used to produce the exhaust. It is so light you can flex it with your fingers squeezing it. This is what you get with cheap eBay exhausts. Yes it works but there is a reason companies like Borla Magnaflow Corsa Tomei Apexi Nameless Perrin ect cost so much. They have a good reputation and have the consumer in mind for an end result instead of making a cheap quick $. If the cheap eBay exhaust fails rusts cracks you just accept the inferior design and buy another. If there is a problem with one of the above companies, expect customer service and a replacement.

Component Wt. %

C Max 0.08
Cr 18 - 20
Fe 66.345 - 74
Mn Max 2
Ni 8 - 10.5
P Max 0.045
S Max 0.03
Si Max 1

[stevo585]

Originally Posted by celek

Your statement is incorrect 304 is 304.
In order to be considered 304 the mixture in the metal has to be defined as below. The problem with Chinese 304 cheap stainless is they go minimum % of Chromium (Cr) and Nickle (Ni). and Maximum of cheaper materials like Iron (Fe) and Carbon (C)

This is why the Metal is cheaper and less of a quality, Although it fall within the constraints of 304 stainless it is a less quality material. Too much Carbon and the steel is brittle, too much Iron and it oxidizes faster. Not enough Chromium and Nickle causes rust spots. They also go extremely thin on the sidewall of the exhaust for minimal material used to produce the exhaust. It is so light you can flex it with your fingers squeezing it. This is what you get with cheap eBay exhausts. Yes it works but there is a reason companies like Borla Magnaflow Corsa Tomei Apexi Nameless Perrin ect cost so much. They have a good reputation and have the consumer in mind for an end result instead of making a cheap quick $. If the cheap eBay exhaust fails rusts cracks you just accept the inferior design and buy another. If there is a problem with one of the above companies, expect customer service and a replacement.

Component Wt. %

C Max 0.08
Cr 18 - 20
Fe 66.345 - 74
Mn Max 2
Ni 8 - 10.5
P Max 0.045
S Max 0.03
Si Max 1

First of all you really can't prove what your saying its speculative. Also its iron particles on the surface that causes the rust spots. This is why you passivate as I mentioned earlier. Something to not do and lower cost as well.

And no 304 is 304. If the chemistry falls in those composition ranges its 304 SS. No other name. From what I read the cheaper chinese exhausts often use the cheaper 201 SS. The US and Japanese exhaust are more expensive because 1. you pay for their higher labor rates and engineers 2. Better quality control and possibly a thicker gauge material and or a "certified" 304 with a material CoC.

My main point is exhaust is probably one thing you can cheap out on. Nothing bad will happen. SS is almost certainly better than the factory mild steel piping.

[prj3ctm4yh3m]

have any rallycross photos?

do you disable the ABS?

do you have a locking diff?

[celek]

Ill just take my 25 years of industry and car experience and sit here quietly from now on