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I am so close to taking my VX to an ocean city. I am worriedas I see some sign of rust on the muffler.
Will a stainless steel exhaust NOT rust at all ?
Can I get a similar to VX OEM muffler/exhaust system that sound just like the OEM muffler ?
Thx
James
anyone ?
Stainless steel will not rust at all, i do build custom stainless mufflers and have sold a few on the site. Check out my site if you re intrested: www.morgan-tec.com
;Dr;
The Truth About Stainless . . . . . . . . . . . . . . . . . . . . . .
Stainless Is Not Really Stainless
Although stainless is more resistant to corrosion than mild steel, the name of the metal is misleading. Stainless Steel is NOT stain or rust proof! When used in contact with chloride salts," (the salt used on roads to melt ice) "sulfides, or other rusting metals, Stainless Steel will discolor, rust or even corrode! Irreversible pitting will develop under rust that remains on stainless steel for any period of time."
Can stainless steel rust ?
The corrosion resistance of stainless steel is based on the formation of a very thin passive layer on its surface. Corrosion occurs when this passive layer is destroyed. The permanence of stainless steel depends on the right choice of steel, the correct processing as well as on the appropiate chemical post-treatment through pickling and surface passivation. Furthermore, the corrosion resistance depends on the surface, i.e. the smoother and more homogeneous the surface is the higher the corrosion resistance will be. Caused especially by inclusions or depositions, e.g. processing-related impressed rust or dust particles, fast-spreading local corrosion can occur.
The following kinds of corrosion can occur with stainless steel:
Intercristalline corrosion
Intercristalline corrosion develops when critically-shaped chromium carbide molecules are formed at grain borders thus causing a chromium depletion in the surrounding area which in turn means the loss of the passive layer effect.
Intercristalline corrosion can be easily avoided by limiting the carbon content to 0.04% or by alloying with Titanium and Niob. The materials 1.4541, 1.4571 and 1.4435 are resistant to intercristalline corrosion.
Localized seletive corrosion
With this type of corrosion the passive layer gets destroyed only at certain points. As a consequence, small pits or holes develop on the surface. Localized selective corrosion is basically caused by halogen ions, especially by chloride ions and can be avoided by a sufficient passive layer and by constantly regenerating the passive layer with oxygen.
In the case of increased chloride ion additions, an appropriate response would be to use a stainless steel containing molybdenum additions which can also generate sufficient resistance. Localized selective corrosion should in any case not be underestimated; it can be often observed in water supply and waste water systems since we will often have to deal with chloride and chloride ions in these situations.
Stress corrosion
This kind of corrosion is named according to intercristalline fissure lines that are developing here. Three simultaneously occuring conditions have to be given:
* presence of tension stress on the surface;
* presence of a specific acting medium;
* prior disposition of the used material for stress corrosion.
Stress corrosion can be prevented through constructive design and the right choice of material. The specific media, however, that are responsible for stress corrosion are rarely found in water and drinking water so that we will not encounter this kind of corrosion, either.
Reduction corrosion
With this type of corrosion the surface is attacked evenly; the corrosion is measured as decrease in thickness per year. The corrosion related decrease is determined in laboratory tests for various media and various materials. The results are published in so-called resistance tables. This kind of corrosion can be entirely ruled out through proper choice of material and can be precluded with austenitic materials that are used in the areas water-waste water.
Contact corrosion
Contact corrosion is a very common form of corrosion that develops when metallic materials with different electrochemical potentials physically touch each other in the presence of an electrolyte. In this situation, the lower-grade metall will be attacked by the electrolyte and will go into solution. The extend of the corrosion depends on the strength of the current in this galvanic cell.
We encounter contact corrosion very often. A commonly known example is the connection between steel pipe and stainless steelpipe. Contact corrosion is also common when cast flanges are attached with stainless steel screws.
Contact corrosion can be prevented or reduced by insulating the metals at the points of contact, by keeping electrolytes away from the metals (move contact areas into dry environments), through constructive measures that avoid contact between cathode areas and very large anode areas.
Crevice corrosion
Crevice corrosion occurs when the stainless steel´s passive layer is destroyed, for example through aggressive media and a concurrent lack of oxygen. For this reason, crevice corrosion can often be found in narrow gaps and in small cavities, e.g. underneath seals, underneath the heads of screws.
Stainless will most likely outlast galvanized or aluminized regardless.
Yup, but it can be more brittle - whatever muffler you get, make sure it is properly supported so the weight is not tranferred to the in/out sections or more importantly the entire exhaust system which has been known to crack and break at the passenger side manifold mount.
It would be interesting to know of those who have had this problem, how many had changed to aftermarket muffers?