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Discussion Starter #1
While it was a pain in the butt, I successfully installed the Mountune SSC this weekend.

The good news is the SSC got rid of the whistle bottle howling noise. But now I get this screeching noise under hard acceleration. It’s not too loud nor is it annoying as the old whistle bottle noise, but it is noticeable. Is this normal?

20-sec clip below captures the noise in question:


Mods currently installed:
1. Mountune B3 kit
2. NGK cold plugs
3. Mountune Sound Suppression Chamber

Upcoming mods:
4. TS 14 lbs. WGA (going in next weekend...hopefully)
5. Mountune Uprated Air Recirculation Valve (still on backorder from the B3 kit)
6. PCV catch can
7. Mishimoto Intercooler kit (on pre-order)
 

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Check the clamp around the silicon "cap". Sounds like air is escaping from the sides.
 

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Discussion Starter #6
So having checked the silicone cap this evening, it was definitely clamped down tight with the metal bracket. Snap ring was also in place.

However, one thing I did notice is the black anodized aluminum housing – the one with a silicon ‘O’ ring attached – can rotate with relative ease.

I wouldn’t call it loose or anything, but certainly makes me wonder if the O ring doesn’t have a tight enough seal.

Is it suppose to rotate easily? Could it be a manufacturing defect? I’m going to give Mountune USA folks a holler and see what they make of it.

In the meantime, I’ll enjoy the faint supercharger-like whine :)
 

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Normal that it rotates.

Circlip/snapring : This is the most common type of retaining ring. Circlip rings can be snapped onto a shaft or inserted into a groove, and they allow a component to rotate axially along its joint while inhibiting lateral movement.


The screeching may be caused by throttle closing to reduce aggresive boost
The air passing through the throttle body is "pinched" and this causes the screeching.
 

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Thanks for the tip! I will take a look a tit tonight after I get home. Will report back with my findings. Hopefully the snap ring didn’t pop out *shudders*
Was the o-ring "dry" when you installed it? I applied a tiny bit of oil on the o-ring, both for ease of installation and for better sealing.
 

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+1 on the AEM dryflow. No unwanted sounds.
Another +1 on the AEM DryFlow. Just installed mine this morning. No increase is induction noise, and noticeable, to me at least, increase in responsiveness of the car. Kinda like going from Normal to Sport mode.
 

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Discussion Starter #13
Thanks for the feedback all. I’ve been in a touch with Mountune support and they will be sending me a replacement unit.

The bad news is I’m going to have to go back in and get that circlip off again :-(. Well, this time I ordered one of those el cheapo mini snap plier set. Hopefully it’ll go off easy this time. I’ll also grease up the O ring during the next install with a high temp high viscosity grease just to be safe. I’ll update again with my findings.
 

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Discussion Starter #14 (Edited)
Update - after sending datalog back and forth few times with [email protected], the issue turned out to be a lose hose on WGA. The hose actually popped off the stock wastegate actuator! How about that.

Upon analyzing the datalog, boost pressure was hitting 30 lbs. with peak torque at 520 lb-ft (EDIT: to clarify, this is the “estimated torque” column in the datalog). No wonder the car felt unusually strong. On the other hand, I am glad the engine didn’t blow up and the issue was caught early on.

With the hose attached, the car now sounds normal.

Here’s the datalog in question that set off the alarm. Phew!

https://1drv.ms/u/s!An9QaLhANagm6TvdR55ZV4bfHzeB
 
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