[S68 X5MC]

Originally Posted by GT500R

Nice, but stainless of only 1.3 mm? Did I read that right?

Yeah, same as the titanium thickness.

[x622]

Originally Posted by S68 X5MC

Yeah, same as the titanium thickness.

That is super thin for stainless.

[S68 X5MC]

Originally Posted by x622

That is super thin for stainless.

Says who?

Edit: Someone needs to measure the stock piping thickness. I'm curious what they put on these from factory.

[jcm3]

most of the aftermarket exhaust pieces ive measured have been 16 gauge (1.3mm)

[S68 X5MC]

Originally Posted by jcm3

most of the aftermarket exhaust pieces ive measured have been 16 gauge (1.3mm)

16 guage is 1.6mm

[jcm3]

sorry that was a typo...1.6mm not 1.3mm. 1.3mm is for aluminum 16 gauge. Stainless is 1.6mm.

[S68 X5MC]

Originally Posted by jcm3

sorry that was a typo...1.6mm not 1.3mm. 1.3mm is for aluminum 16 gauge. Stainless is 1.6mm.

Not sure what company's exhaust is made with aluminum. Either way, 1.3mm will do just fine considering it's harder than stock systems and .3mm difference.

[x622]

Originally Posted by S68 X5MC

Says who?

Edit: Someone needs to measure the stock piping thickness. I'm curious what they put on these from factory.

As others have replied, typical thickness is 1.6mm or .0063" and using a heavier gauge metal generally reduces drone within the range our ears detect. This happens because thicker exhaust walls raise resonant frequencies shifting them higher on the spectrum and out of the drone generation trouble spots in the RPM band. For example, the exhaust on my x3m doesn't drone at all because it's thickwall and copied off a proven design.

In short: Thicker metal = stiffer structure = higher natural frequencies. While the number of vibration modes stays the same, each mode occurs at a higher frequency. As a result, the resonance peaks move upward, reducing the likelihood of experiencing audible drone.

[S68 X5MC]

Originally Posted by x622

As others have replied, typical thickness is 1.6mm or .0063" and using a heavier gauge metal generally reduces drone within the range our ears detect. This happens because thicker exhaust walls raise resonant frequencies shifting them higher on the spectrum and out of the drone generation trouble spots in the RPM band. For example, the exhaust on my x3m doesn't drone at all because it's thickwall and copied off a proven design.

In short: Thicker metal = stiffer structure = higher natural frequencies. While the number of vibration modes stays the same, each mode occurs at a higher frequency. As a result, the resonance peaks move upward, reducing the likelihood of experiencing audible drone.

False, the diameter is the main factor in drone, not thickness.

Edit: I'm not going back and forth on this, it'll be just fine.

[x622]

Originally Posted by S68 X5MC

False, the diameter is the main factor in drone, not thickness.

Edit: I'm not going back and forth on this, it'll be just fine.

I don't think I ever said thickness was the main or only factor. Both absolutely factor in. Why do most thinwall titanum exhausts sound higher pitched? Reason: Thinwall.

[S68 X5MC]

Originally Posted by x622

I don't think I ever said thickness was the main or only factor. Both absolutely factor in. Why do most thinwall titanum exhausts sound higher pitched? Reason: Thinwall.

No, titanium exhaust tends to be thinner and smaller in diameter like Valvetronic. The stainless 80mm diameter with a 1.3mm thickness will be fine without drone. This isn't my first rodeo.

[x622]

Originally Posted by S68 X5MC

No, titanium exhaust tends to be thinner and smaller in diameter like Valvetronic. The stainless 80mm diameter with a 1.3mm thickness will be fine without drone. This isn't my first rodeo.

What? Valvetronic is a chinese dropshipper ran by some kids. They are the one who spec it. Both factors are why the exhaust is higher pitched.

You are correct that most titanium exhausts are thinner wall, but you are correct that 80mm with a 1.3mm thickness will likely be fine even though it's a little thin.

[S68 X5MC]

Originally Posted by x622

What? Valvetronic is a chinese dropshipper ran by some kids. They are the one who spec it. Both factors are why the exhaust is higher pitched.

You are correct that most titanium exhausts are thinner wall, but you are correct that 80mm with a 1.3mm thickness will likely be fine even though it's a little thin.

Yeah, and I'm excited af to get it. 😆

For anyone else buying. They have Chinese New Year coming up and production will take a bit longer. He estimates receiving my exhaust around February 20th. I can't complain when they're custom making these things for us.

[x622]

Originally Posted by S68 X5MC

Yeah, and I'm excited af to get it. 😆

For anyone else buying. They have Chinese New Year coming up and production will take a bit longer. He estimates receiving my exhaust around February 20th. I can't complain when they're custom making these things for us.

In for results. Think it'll work with pre-lci or did they completely change everything? Haven't thrown a LCI on the lift to see if it looks different.

[S68 X5MC]

Originally Posted by x622

In for results. Think it'll work with pre-lci or did they completely change everything? Haven't thrown a LCI on the lift to see if it looks different.

It's the same other than the secondary connection flanges. Of course, the primary and secondary sizes swapped which worked out for me. The pre-LCI secondary would have sucked to get out.

Edit: I found something interesting and asking about it on this thread.
https://g05.bimmerpost.com/forums/sh...&postcount=149