AdamIsAdam

Was this answered?

Paulywanacracker

No, because it's Top Secret?

Westcoast

Well... if the inner diameter of the pipe is 25mm then the outside is a lot bigger than 18-22mm!

houstonbuckeye

Thank you for posting.
WARNING: I've accessed there engine twice and shredded my hands and fingers both times. The area around the engine and beneath the intake manifold are full of metal clips and securing pieces the are as sharp as knives.
BTW: John and the folks at Soul are extremely customer focused and a pleasure to work with.

houstonbuckeye

The caps from Soul are 25mm and are a tight fit over the pipes (just as you would want). I struggled to get them over the pipes, so after a while I applied some grease to the inside of the cap. This seemed like a plausible idea until between the grease and my sweat the little bugger jumped out of my hand and landed somewhere in the bowels of the engine compartment. Sometime soon I'll lift the car and take the 30 minutes required to remove the underbody panels where I hope to find the cap.
I called Soul to enquire about getting another cap, left a message and long after business hours John called me back and told me not to worry, she'd take care of it. These are some wonderful folks at Soul.

Westcoast

You're welcome, I found that if you don't shed a little blood then you can't possibly be one with the machine...

As for the caps, perhaps softening them in a bowl of hot water before installation would help?

I had the "you've got to be kidding me" experience during installation of the valve controller, watched as a locking tab flew up and over my hand to disappear into the depths... I figured if I wanted it back I would have go after it right away as there are openings in the bottom trays.

About an hour later I was back to where I had left off.

houstonbuckeye

I ended up disconnecting the vacuum line to the diaphragm valve on the symposer line. I left the line in place as I didn't have a way to cap both the open ends if I removed the symposer line.
The valve controller was a particularly brutal bit of work. I pretty much followed Janko's video, but getting my hand far enough down to disconnect the controller electrical connection was an exercise not to be repeated. Of course once the plug is disconnected there is no turning back. Fortunately plugging the valve controller into the electrical plugs was much easier than I feared it would be. After securing the controller box and wiring and cleaning up all the blood I dripped all over the intake and the engine compartment surround, getting the cover, etc. was pretty easy.
Now to find that little red cap.

Paulywanacracker

Thank You, this stands to reason.

I was wondering; If the 25mm fits very tight, but fits nice and snug with warming, how should the 26mm fit? Very loose? Or just right?

houstonbuckeye

26mm should be fine. Regardless of how tight it seems to fit, I would use a zip-tie to secure the cap,

Westcoast

Sorry, I didn't measure the outer diameter of these, nor did I go this route, I installed the internal plugs seen earlier in the thread.

It would make sense that Soul choose the closest standard size that could be stretched over the fitting ends to proved a good seal.

fueledbymetal

Does this make a noticeable difference when cruising at ~75mph in 6th w/ the manual transmission?

DerekHK

Hihi, I'm planning to take the whole Sound Symposer out. Can someone tell me all the materials I need for this mod? I see there are many different kinds of plugs etc. I just want to make sure I have everything before this mod. Thanks in advance!
I think I will order some Dynamat or Second Skin sound deadening material. What else do I need? What kind of plugs and how many of them? Thanks!

Bob Z.

https://rennlist.com/forums/718-gts-...ispreloading=1

Start at Page 1.

houstonbuckeye

I removed the symposer line between the vacuum activated valve and the plastic piece that transmits sound through the firewall.
I installed 1" drain plugs purchased on Amazon, . I used zip ties to secure the plugs to the lines into which they are inserted so they wouldn't end up rattling around the engine bay if they were to come loose.
I also disconnected the vacuum line for the valve actuator, capping the metal line with a rubber cap purchased at a local auto parts store. The lines were secured using zip ties
Parts I used: 2 x 1" drain plugs (Amazon), rubber cap (purchased in a package of various sizes) and zip ties.
I tried rubber caps, but was not able to stretch them over the open tubes.
Once you have access to the engine, the job is simple. But it is challenging to work in such a small area that is not particularly easy to reach.

AdamIsAdam

@houstonbuckeye did you notice a difference in sound? (which car do you have again?)