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Discussion Starter #61
...Once the packing blows out will drone be present or will
the muffler just not reduce decibels as much?...
Per our supplier..."If the material blows out, the drone will not be impacted. The dBs will rise and the exhaust note will get raspier." They also stated that the material will withstand 1200 deg F with bursts to 1650deg.
 

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1200 would mean that it's fiberglass of sorts. EGTs are 14-1600 in the header on track cars. The exhaust is very short so the EGTs at the muffler normalize to something not much less than what is seen in the header in cars with some horsepower. The U-bend will be red hot in a 20 minute session.

All packing will blow out. Stainless steel "scrubble" is the go-to standard for serious abuse. F-glass turns into glass beads in a race or two...

The fire balls that are referred to are decel fuel over-run and is a product of all Lotus 2ZZ cars running any reasonable decel cut-- including the stock Lotus ECU configuration. Fireballs on decel are actually a very cold flame compared to 1500F combustion temps...

Nice idea on the chambered exhaust.

-Phil
 

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Discussion Starter #63
Yes, it was. AFAIK every traditional packing material will "blow out" eventually, even stainless steel. The only packing material I know of that won't "blow out" is lava rocks, which are sometimes used by the guys who race rotary motors at LS and need to pass sound. Anyway, I'm really just curious if this is a newer/non-traditional packing material.

Also, are these only going to be available with the welded on brackets? Or down the road will you switch to a non-fixed bracket?
Thanks.

Track use will generate high EGTs but the track cars that I've run with Katanas have done well with the TRACKpipe. Admittedly, I've never cut them open but the dB levels don't appear to have changed. But I also wear earplugs while on track...

Lava rocks would be a hilarious new idea. Maybe even a joke we should come up with a muffler full of it...:D

No, we don't have plans to do it with non-fixed brackets.
 

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Discussion Starter #64
...EGTs are 14-1600 in the header on track cars. The exhaust is very short so the EGTs at the muffler normalize to something not much less than what is seen in the header in cars with some horsepower. The U-bend will be red hot in a 20 minute session...
I've not seen EGTs that high but I don't doubt some (not most) cars experience it. EGTs lose about 100deg per foot before hitting the muffler. So the temps in the muffler will be closer to the acceptable range for our material.

Power = heat, so I'd agree that big hp cars should consider rebuildable systems if keeping dBs down (even for a short period of time) is desirable.
 

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Discussion Starter #65
My sector111 "TRACKpipe" blew out the packing in less than a year on my stock 220S, so is your new muffler using different material?
Here's the answer from our supplier:

The older muffler we made where built with stand needle matt fiberglass. This is still a good high temp fiberglass but nothing like the continuous strand fiberglass system we use today. We made a substantial investment in this process and I truly believe it is the best direction.
 

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I've not seen EGTs that high but I don't doubt some (not most) cars experience it. EGTs lose about 100deg per foot before hitting the muffler. So the temps in the muffler will be closer to the acceptable range for our material.

Power = heat, so I'd agree that big hp cars should consider rebuildable systems if keeping dBs down (even for a short period of time) is desirable.
Shinoo,

I think your estimate of 100 deg/ft is correct when the exhaust heat does not get a chance to reach the operating temps that are seen during track use. Once the temp of the exhaust gas is given a chance to bring the whole exhaust up to temp, you are not going to drop near that many degrees per foot. If you figure that the catalytic convertors won't survive track use, I would believe that this leads to justification of the high gas temps that the muffler is going to see.

Just my 2cents.

I would love to get rid of the drone and noise level of my exhaust but I also need the center diffuser exit since I run a blown diffuser.

Later,
Eldon
 

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Shinoo,

I think your estimate of 100 deg/ft is correct when the exhaust heat does not get a chance to reach the operating temps that are seen during track use. Once the temp of the exhaust gas is given a chance to bring the whole exhaust up to temp, you are not going to drop near that many degrees per foot. If you figure that the catalytic convertors won't survive track use, I would believe that this leads to justification of the high gas temps that the muffler is going to see.

Just my 2cents.

I would love to get rid of the drone and noise level of my exhaust but I also need the center diffuser exit since I run a blown diffuser.

Later,
Eldon
Exactly, the f-glass filling that doesn't just disintegrate and fly out the tail pipe literally turns to little glass beads. I literally have 2 dozen mufflers in the barn in this condition from every manufacturer. The muffler will maintain temps well in excess of 1200F on the track with a supercharged car as the short exhaust system begins to normalize in temp...

Here's a car on the dyno as the exhaust heats up. (had a "Vonhep" muffler. We still see those from time to time. The aluminum end caps literally will melt on these cars). 270whp car, so nothing crazy... You can see the u-bend turning red and looking closely, can see the 02 sniffer turning red in the tip...

Stainless starts turning red where you can see it around 1200 and glowing bright red/orange at 1500 or so... Here you can see the 1500 temps at the header... 1200 or at the u-bend... in another 5 minutes on the skinny pedal, well, you get more normalizing... the inside air is hotter than the tube it flows through...

Anyway, I'd guess it's a fine muffler, but repackable mufflers exist for a reason. Even with 100% stainless scrubble, there will be considerable packing consumed in a single season.


-Phil
 

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Shinoo - Thanks for developing a muffler that reduces drone! The drone is probably one of my biggest annoyances, especially while cruising on the freeway. As long as they are still available sometime next year or so I hope to pick one up! ...With an upcoming wedding I have to limit my car spend!

Phil - Thanks for those photos! I didn't realize that the U-bend got so hot (but it makes sense)! Are there any concerns with the bend in particular starting a fire or damaging the clam? I removed the metal heat-shielding and applied header wrap so hopefully that helps a bit...
 

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Discussion Starter #69
...270whp car, so nothing crazy...
Those are sweet pix but not applicable to my target clients. That is over 300hp at the crank, which is NOT common. I agree that the exhaust system can get red hot - especially on a dyno. This will not happen to the vast majority of Lotus owners - even on a track.

Killing drone was our main goal not track durability. I know that most clients are running less the 250hp and drive mostly on the street and occasional track. For these folk, a repackable muffler is a maintenance headache that they can/should avoid.
 

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Temperatures aside, the gas pressure alone will rearrange the packing in any non-baffled muffler. As the supplier stated, the drone won't change because the anti-drone device is rigid unlike the packing material. Shinoo has made it clear that this is a street muffler, so sustained temps will be hugely lower especially since cooling air is present in spades (unlike on a dyno even with fans).

There, does that consolidate everything well? All parties seem to be making true statements but the context here is important. If you were happy with your non-rebuildable muffler before, then you won't have an issue here.
 

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Shinoo,

I think your estimate of 100 deg/ft is correct when the exhaust heat does not get a chance to reach the operating temps that are seen during track use. Once the temp of the exhaust gas is given a chance to bring the whole exhaust up to temp, you are not going to drop near that many degrees per foot. If you figure that the catalytic convertors won't survive track use, I would believe that this leads to justification of the high gas temps that the muffler is going to see.

Just my 2cents.

I would love to get rid of the drone and noise level of my exhaust but I also need the center diffuser exit since I run a blown diffuser.

Later,
Eldon
Off topic, but can you post a pic of the blown diffuser. I also have a semblance of a blown diffuser.
I cut a 3" diameter hole in a diffuser cover delete plate and then cut the exhaust pipe nearly flush with the diffuser. -Robert
 

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Off topic, but can you post a pic of the blown diffuser. I also have a semblance of a blown diffuser.
I cut a 3" diameter hole in a diffuser cover delete plate and then cut the exhaust pipe nearly flush with the diffuser. -Robert
That air flow does NOT help the diffuser at all. A blown diffuser will use the exhaust to create air flow in the same direction the air would be flowing. It also needs to flow parallel to the air flow otherwise it disrupts what it is trying to help.

Technically, you can not create a blown diffuser on our cars because you cannot turn the motor into an air pump when you are decelerating. To do this, would have to cut the ignition and fuel and leave the throttle wide open.

Later,
Eldon
 

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Hi Shino

one big request can you get some certifications for the exhaust system??? i have been looking for a certified exhaust for my exige for the longest time as here in singapore i cant get a single exhaust approved or street legal or changed due to the requirements locally if possible we can talk via email or something to let u understand my current problem here ?

im still using the stock exige muffler i cant change to any at all!!

i really hope you can help the local community here !!!!

Gerrayne
 

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Discussion Starter #74
one big request can you get some certifications for the exhaust system???
What certification is required? Feel free to email me direct with the details: shinoo 'at' inokinetic.com
 
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