those, yes
Coupe King Stainless Exhaust Refinement
- Thread starter E9Wayne
- Start date
those, yes
if you would have been taught a bit about steel and metallurgy you would have known that SS: a) it is not steel and b) it rusts ;-)
Wladek
Well-Known Member
Average black steel / carbon steel, it is: iron with up to 2% carbon in it + up to 1% mangan + other content less than 1%.
Good quality stainless steel, it is: iron with up to 1,2% carbon in it + ca. 18% chrome, ca. 8% nickel, ca. 2% mangan & +- almost the same other content as in black/carbon steel.
Ok, good quality/very good quality SS have about 28% more additives in iron, but you can't say that it is not steel.
Admittedly the chrome exhaust tip is also one of my favorite subtle features. I've been on the fence about an SS exhaust but because of the lack of chrome tip and that my rusty original steel exhaust sounds so good with the center can removed I've decided to keep it.
It is not.
Once Cr transforms the Fe-C diagram SS lays out of the area of steel denomination. That is why
deQ, i understand what you mean, but stainless steel has most of the exact same structural properties as regular steel. aluminum and other alloys are quite different. that being said, you can look at different steel formulas and you will find different strengths / given area. that doesn't mean they aren't steel ... just different.
does stainless rust - some do / some don't ... it largely depends on what the stainless matrix is and what it is exposed to. most of the formulas take plenty of neglect for them to rust.
does stainless rust - some do / some don't ... it largely depends on what the stainless matrix is and what it is exposed to. most of the formulas take plenty of neglect for them to rust.
316L Stainless resists rust but high salt concentrations will still cause pitting
Regardless of one's disposition on exhaust metal type, wouldn't it be possible to fit a chrome exhaust tip onto a stainless steel tail piece? Perhaps this is a winning combination for some.
Wayne - I want to hear your coupe now; we need to get together.
One comment on your change -- As you know I do almost all of my own work. The joint that has been removed from your exhaust makes removing the exhaust from the vehicle much easier for one person when working on anything on the rear axle. With the way your exhaust has been changed, you would need to unbolt the exhaust at the manifolds in order to drop the exhaust, and I think you would need to raise the vehicle fairly high off the ground in order to have room to wiggle the front part of the exhaust free. If you look at Sven's exhaust, he has a pair of flanges incorporated into his exhaust; one forward and one aft of the cat. This makes removing all or part of the exhaust much easier. I would suggest you have your exhaust shop put a pair of flanges into your system; one forward of the cat to replace the one they cut out and another to replace the other joint that Coupe King uses near the right rear half shaft, as Sven has done.
One comment on your change -- As you know I do almost all of my own work. The joint that has been removed from your exhaust makes removing the exhaust from the vehicle much easier for one person when working on anything on the rear axle. With the way your exhaust has been changed, you would need to unbolt the exhaust at the manifolds in order to drop the exhaust, and I think you would need to raise the vehicle fairly high off the ground in order to have room to wiggle the front part of the exhaust free. If you look at Sven's exhaust, he has a pair of flanges incorporated into his exhaust; one forward and one aft of the cat. This makes removing all or part of the exhaust much easier. I would suggest you have your exhaust shop put a pair of flanges into your system; one forward of the cat to replace the one they cut out and another to replace the other joint that Coupe King uses near the right rear half shaft, as Sven has done.
- Messages
- 392
- Reaction score
- 230
Chris, thank you. Clearly, this is not something I thought about in advance but now that you point it out, I have some regrets about not taking more time to think this through. If I do go back to the shop to have Sven's rear muffler installed for further quieting and mellowness, I'd have them install at least one flange. Thanks buddy and Blue Belle is ready to see Annabelle when you are...Cars and Coffee soon if the weather is good.
I’ve been thinking about doing something like this also. Would it cause too much back pressure to narrow the exhaust tip on the coupeking exhaust and then fit the chrome tip? I might try a different muffler too.
WHy would you do this? Wouldn't a 60mm exhaust tip work? Found cheap on ebay ($20). Just search for early Porsche. A tad shorter than original, but don't think anyone would notice.
keep in mind that the CK exhaust has the end of the tailpipe finished with a flange (tip folded up). depending on the OD, you could cut it slightly and put a tip on it.
I guess I thought the tip was too wide for a 60 mm tip. It just looked much bigger. I might be wrong. You’d think I would have just measured. But it’s at the shop and my other cars are at my garage. I’ll look and figure it out.
- Messages
- 392
- Reaction score
- 230
Hey Sven, I did some research and found a good custom exhaust place near me and ordered the Magnaflow muffler 122886 from Amazon. They tried fitting and said it was too large for the available space and showed me that the max length is 22" and preferably 20" versus the 24" length this muffler measures. Do we have the same part number here? They also removed the catalytic convertor I installed a few months ago because I was beginning to feel some reduced power and weird idle characteristics once the cat was worn in. They re-installed my previous straight flange like I had from Coupe King and we agreed we would resume this research after car show season. This shop can even cut down the new Magnaflow muffler I ordered and install more baffling if needed, but it would be much simpler to find a rear muffler not exceeding 22" in length or having these guys cut into the round muffler I have now and install more baffling....Or maybe there is another rear muffler out there that is 2.5" in and out....
Wayne,
The 12286 fits in the back. It is 24" long (5x8 oval cross section). You have to bash in a dent so it clears the rear diff mounting flange. You can see it in the pictures earlier in the post. Perhaps the shop could cut and re-weld a depression instead of using a hammer to craft.
The 12286 fits in the back. It is 24" long (5x8 oval cross section). You have to bash in a dent so it clears the rear diff mounting flange. You can see it in the pictures earlier in the post. Perhaps the shop could cut and re-weld a depression instead of using a hammer to craft.
- Messages
- 392
- Reaction score
- 230
Finally, a more quiet Coupe King stainless exhaust system!
Hey folks, well it took a few years to come back and address my loud exhaust, but I finally found a solution I like. To recap, a few months ago, some of you may recall my tow truck fiasco incident whereby my E9 started to roll off the flatbed because a tie down cable came loose and my car bottomed out on my center resonator which prevented it from careening off the back of the flatbed onto Tom Baruch's driveaway. A pretty cheap crushed resonator as an "emergency brake" was a small price to pay for what could have been $$$ in the frame and body shop!
So I went in to my local custom muffler shop this morning to talk with them about ways to quiet my system but also replace the crushed center resonator with a new Magnaflow piece I just bought. I also wanted to show them Sven's larger rear can solution to see how that would fit and they said no problem to that too. But I'd have to come back with that part at a later time for that switch...
First things first, removing the center resonator to install my new one. They showed me the inside of the Magnaflow resonator which was quite literally a pipe with some perforations in it. The shop told me this is a big part of the noise reduction challenge was simply getting another resonator with more baffling. They had a piece in stock (made by AP Emissions Technology, part #4218113S) and it cost $50. When they showed me the inside of this replacement resonator (see second photo) it was clear there was more sound reduction tech inside including two chambers versus one on the Magnaflow unit. So I okayed the switch to the AP piece and they welded it it. Right away on startup I could tell my exhaust was finally quieter and even more refined sounding! A short test drive showed no difference in acceleration or backpressure issues, plus there was less "crackling" sound off throttle with my Magnaflow unit. The new resonator is 18" long versus the Magnaflow at 22" btw.
I'm going to live with this solution for some time and ponder if I need to go to the next step and adopt Sven's cool solution with the rear can.
But I'm super enthusiastic thus far and my hearing will probably last years longer as a result!
And if anyone needs a brand new Magnaflow center resonator (#10436) I'll be selling that for $75 plus shipping.
@Ohmess you need to try this out!
Hey folks, well it took a few years to come back and address my loud exhaust, but I finally found a solution I like. To recap, a few months ago, some of you may recall my tow truck fiasco incident whereby my E9 started to roll off the flatbed because a tie down cable came loose and my car bottomed out on my center resonator which prevented it from careening off the back of the flatbed onto Tom Baruch's driveaway. A pretty cheap crushed resonator as an "emergency brake" was a small price to pay for what could have been $$$ in the frame and body shop!
So I went in to my local custom muffler shop this morning to talk with them about ways to quiet my system but also replace the crushed center resonator with a new Magnaflow piece I just bought. I also wanted to show them Sven's larger rear can solution to see how that would fit and they said no problem to that too. But I'd have to come back with that part at a later time for that switch...
First things first, removing the center resonator to install my new one. They showed me the inside of the Magnaflow resonator which was quite literally a pipe with some perforations in it. The shop told me this is a big part of the noise reduction challenge was simply getting another resonator with more baffling. They had a piece in stock (made by AP Emissions Technology, part #4218113S) and it cost $50. When they showed me the inside of this replacement resonator (see second photo) it was clear there was more sound reduction tech inside including two chambers versus one on the Magnaflow unit. So I okayed the switch to the AP piece and they welded it it. Right away on startup I could tell my exhaust was finally quieter and even more refined sounding! A short test drive showed no difference in acceleration or backpressure issues, plus there was less "crackling" sound off throttle with my Magnaflow unit. The new resonator is 18" long versus the Magnaflow at 22" btw.
I'm going to live with this solution for some time and ponder if I need to go to the next step and adopt Sven's cool solution with the rear can.
But I'm super enthusiastic thus far and my hearing will probably last years longer as a result!
And if anyone needs a brand new Magnaflow center resonator (#10436) I'll be selling that for $75 plus shipping.
@Ohmess you need to try this out!
