To stainless or not to stainless?

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JMather
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To stainless or not to stainless?

Postby JMather » Thu Apr 30, 2009 8:38 pm

Ok I'm a 3 year apprentice boilermaker so I thought what the hell why should I pay $900 for a stainless exhaust when I can do it at cost of materials. I'm pretty handy with a tig. :lol:
So just before I decided on the type of exhaust materials I thought I should see what everone thinks. Should I go stainless or mild steel?

Also it's a bit off topic but what I was going to do was one of 2 things.
1) a 'Y' piece to two mufflers.
2) the normal twin exhaust setup on mx's.
3) One muffler to a 'Y'

Oh by the way twin pipe is the only way to go! :wink:

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madboy
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To stainless or not to stainless?

Postby madboy » Thu Apr 30, 2009 9:06 pm

Well, i am taking my stainless headers to get welded up tomorrow, two nice big cracks right at the flange, I understand this is very common for stainless exhausts.

Unless of course you can make sure they never crack :)

project.r.racing
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To stainless or not to stainless?

Postby project.r.racing » Thu Apr 30, 2009 10:01 pm

stainless steel headers is a big no no. cast iron is the way to go for headers.

the rest of the exhaust can be stainless or mild steel.

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Steampunk
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To stainless or not to stainless?

Postby Steampunk » Fri May 01, 2009 12:03 am

mild steel.
mild steel expand and contract less than stainless and thus has less tendency to crack.
There are engineers on this forum who can go into greater detail.
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Matty
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To stainless or not to stainless?

Postby Matty » Fri May 01, 2009 12:57 pm

project.r.racing wrote:stainless steel headers is a big no no. cast iron is the way to go for headers.
.

Right. Guess Mazda got that one wrong then... :roll:

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16bit
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To stainless or not to stainless?

Postby 16bit » Fri May 01, 2009 1:05 pm

ceramic coated, hydro formed inconel x is the only way to go!!!!

http://www.desktopmachine.com/framepic. ... &size=1024
98 evo gold - rotrexed and loving it.

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irwin83r
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To stainless or not to stainless?

Postby irwin83r » Fri May 01, 2009 1:16 pm

16bit wrote:ceramic coated, hydro formed inconel x is the only way to go!!!!

http://www.desktopmachine.com/framepic. ... &size=1024


ha is that your car in the pic? i knew you were going crazy with CF but.. wow youve done some body work..


as far as exhaust goes.. what do you want?
performance?? up high? down low? mid range?
sound?? raspy and loud? low and rumbly? quiet as a mouse?
looks?? twin outlets? single? cannon shot gun style? cannon straight out center?

if i were you and i had the time and skills and wanted something totaly left field and different build a twin pipe system. so two 2-1 extractors into two 2" pipes going through high flow cats a good reasonator (or two hot dogs) and two rear mufflers. dont put a cross over pipe in and later get some lumpy cams fitted.. should sound like a boat at idle :D nice, dis jointed and lumpy :wink:

JMather
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To stainless or not to stainless?

Postby JMather » Sun May 10, 2009 2:55 pm

Well I've already got extractors (not stainless). what I wanted was performance of any kind but not too noisy. How do you get performance down low compared to up high? Twin pipes was a definite with no cannons only going to go mufflers.
Is there any mufflers or hot dog brands I should look at? and does any one have stock exhaust measurements? I don't have my roadster at the moment :cry:

mitch_f1
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To stainless or not to stainless?

Postby mitch_f1 » Thu Feb 18, 2010 8:48 am

irwin83r wrote:
16bit wrote:ceramic coated, hydro formed inconel x is the only way to go!!!!
as far as exhaust goes.. what do you want?
performance?? up high? down low? mid range?
sound?? raspy and loud? low and rumbly? quiet as a mouse?
looks?? twin outlets? single? cannon shot gun style? cannon straight out center?

if i were you and i had the time and skills and wanted something totaly left field and different build a twin pipe system. so two 2-1 extractors into two 2" pipes going through high flow cats a good reasonator (or two hot dogs) and two rear mufflers. dont put a cross over pipe in and later get some lumpy cams fitted.. should sound like a boat at idle :D nice, dis jointed and lumpy :wink:


SO I am looking at getting an exhaust made up for mine. Just bought a set of extrators on eBay 2" outlet. I am also looking at getting a high flow cat (which one??). But as for the rest of the exhaust, what should I do? I had one shop saying "i would run a 2.25 inch mandrel exhaust with resonatorand a step down muffler on the rear 2 inch (speeds up gas flow as gas temp cool down) all in mild steel....and dress it up with a stainless tip." The cost of which would be $500

Basically what I want out of it is just a bit of noise. Did my first track day yesterday, and one of my problems was not being able to hear the car!!! It really pissed me off. So I want to be able to hear it, so it has to be fairly loud, but I also want a bit of performance in the low to mid range. Not worried at all about looks or nothing.

Has anyone got a really good setup for road/race that is loud, but not busting your ears around town loud?

Also, is there any benefit to removing the muffler on a NA car?

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Regie
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To stainless or not to stainless?

Postby Regie » Thu Feb 18, 2010 10:11 am

i just bought one of these cats

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... K:MEWNX:IT

they sell 200cpi's and 100cpi's. as the 100s are road legal i went for the 200..
MY07 NC, Mazdaspeed Body, Ohlins, Full GWR Exhaust, 17x9 RPF1's, 4.1FGR and lots lots more


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