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bit confused now about which exhaust is best- the mild steel or a stainless steel.

whats the noise differances between these metals???

my exhaust at the moment is a custom 3" dump and front (with no cat) in mild steel upto a middle trust muffler, from there its 3.5" stainless to the end cannon which happens to be a hks super dragger.

i was thinking of changin my dump/front to 3.5" but not sure whether to make it stainless or mild???? any pros and cons guys?

how would it sound if i ditched the middle muffler and just had one cannon at the rear (thats it no cat/ mid muff etc) would this be a good idea or not?

really not fussed about legality, so thats not a factor.

engine is rb30det (25 head) should make atleast 300rwkw.

thanx

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Stainless:

is a superior metal.

will last longer.

will looks heaps better.

could be prone to cracking at high temps, but is unlikely (don't quote me)

costs more.

Mild steel:

will do the job just as well as stainless.

is cheaper to buy.

won't last as long but will probably last for long enough while you own the car.

doesn't look as good.

Sound Differences:

Stainless makes a 'ting' sound.

Mild steel makes more of a 'tung' sound.

I'd say stainless would resonate louder.

If you ditched the cat and centre muffler:

Could be on droney side when driving.

It would sound awesome from the outside.

everything I have said is not a professional opinion and is based on my general knowledge.

Edited by KeyMakeR33

Ideally you should insulate the dump pipes (heat wrap or ceramic coat) so it doesn't really matter what metal you use from an asthetics (i.e. bling) point of view.

Mild steel generally handles heat cycling (heating up and cooling down) better than stainless steel and has a lower coefficient of expansion (less likely to crack welds amongst other things).

Ideally you should insulate the dump pipes (heat wrap or ceramic coat) so it doesn't really matter what metal you use from an asthetics (i.e. bling) point of view.

Mild steel generally handles heat cycling (heating up and cooling down) better than stainless steel and has a lower coefficient of expansion (less likely to crack welds amongst other things).

I totally agree with that...in the end...a pipe is a pipe is a pipe...i'd rather have a proper mild steel system with proper welds and bends...also...with mild steel if you get cracks its alittle easier to get it welded up...but that said...stainless steel is alittle lighter...which is always a big plus too...

titanium would be ideal but its would put a semi-permanent scar in my wallet haha

my dump will definately be heat wraped

weight is a factor for me but i dont think there would be a noticable weight differance between the two, ive ditched the back seats for my cage, no a/c condenser or compressor, cf/fibreglass body panels, no big stereo just a deck, etc so that would help.

still undecided... hmmmm, might just leave my exhaust as it is for now, and later buy a apexi n1 3.5" cat back, and get the rest custom job in same stainless 3.5"

If you want to be anal, or if you're interested... :wave:

Mild steel = 7860 kg/m3

vs

Stainless steel (304) = 7930 kg/m3

If you can afford the best, go titanium.

Other than that, I personally prefer the sound from a mild steel system over a stainless one, which is the deciding factor for me.

stainless cannot be ceramic coated they will crack even faster~~ the ceramic stuck on stainless and expand and contract at different rate to stainless and being rigid, the stainless will crack soon enough.....

there is no way mild steel be lighter than stainless, stainless is one of the hardest metal to work with...

I think people use stainless just because they look good also, most Jap aftermarket Xhaust are stainless~~

Mild steel with ceramic coating is more resistant to temperature however will not look as good, more durable I think to temperature changes however not so sure about corrosion

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