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Sound Tube delete

Got my kit fast, thanks to Cool Tech (Kendall)

Took me 30 seconds to remove the old tube, two seconds to pop in the firewall plug and how fast you can tighten a clamp for the rest. For the guys that do not do their own work, don't worry you can do it your self with a 10 MM socket and screwdriver.

For the sound, not too much different. In a way I like it since you can hear the motor better for real not the way it sounds in a tube, if that makes sense. I can also hear the exhaust note a little better (7/8 discs). It is not a grand difference but the whole point is cleaning up the engine compartment anyway.

Old pipe and pipe out


Connection points bare and with Kendall's kit installed. The last is a newer clean look :D

YellowBoss said:
After seeing what happened to VT's cap I figured I would also do something to this setup (although it does look like something chewed at it). I when to Home Depot and found these, they are the same type I use to plug the brake ducts on the street:

The fit was loose so I decided to get the caps that Gary bought. I could not find them in black so I picked up some white ones. While test fitting I saw it would leave little pieces behing (can't see with black?) and I was not happy about that so I put the Cooltech piece inside of the cap. This way it will not suck pieces into the intake, it worked but I was still not happy. I am thinking this will degrade further with the engine heat and FL weather. I had already cleaned the inside before I shot this pic:

I went back to the store and bought the 1 1/2 inch cap. When you tighten it down it works just fine, a little smaller would be better but I feel this is better then the other options. I also left the Cooltech cap inside of this cap.

I have been meaning to post a pic of this hose adapter. It takes up most of the space between the 1 1/2" cap and the fitting on the air intake. You just have to shorten it a little.

Went CoolTech as well for the delete solution with a twist.

Placed a Champagne cork from the bottle popped with my wife and 2 year old son, the day I brought my Boss home to fill in the void in the firewall. I had to sell my 1998 Black/Black Cobra due to a divorce so THIS is a memento I will never give up....... Just goes to show you persistence does prevail :)
pufferfish said:
i'd be willing to bet that happened bacause the end of the cap was drawn into the tube under vacuum repeatedly every time you start the car, let off the throttle, etc. thats exactly why i put a reinforcement into my kit (not trying to sell, just don't want my product lumped into the issue) . the $1.60 crutch foot is good too...but way more function than form for my taste.
I just got a C&L intake which didn't come with a sound tube cap so I was looking over some old posts and read this. The poster whom I quote made an interesting point, though not for the reason he thought. Closing the throttle creates high vacuum behind the throttle body as the engine tries to suck air past the closed blade. At that time there would be virtually no vacuum sucking on the sound tube cap as there is only a slight amount of air flowing through the system. At WOT is where vacuum, or negative pressure, would be created in the intake assembly forward of the TB and where the potential would exist for a weak cap to be sucked into the intake. Now this is where it gets interesting and where I have engaged in endless debates over whether there is any value in an aftermarket CAI. I think it is obvious that the more restriction there is downstream of the sound tube port the harder the engine will be trying to suck in the cap. Imagine if you poked a hole in the cap, plugged in a hose nipple, and attached a vacuum gauge. Then you ran the car at WOT while reading the gauge. Then to simulate a very restrictive intake you cover the air filter with a rag. Intake restriction goes up, power goes down, and the reading on the vacuum gauge increases. The higher the reading on the gauge forward of the throttle body the more restriction exists. This is exactly how I came to the conclusion that the stock intake assembly is restrictive, except I didn't cover the filter with a rag. I merely measured the vacuum in the manner stated above with the stock CAI and then a Steeda CAI. With the stock CAI there was 18 in. H2O more vacuum sucking on the cap than with the Steeda. Anyway, off to Lowes to find a cap.
pufferfish said:
i have over 10k miles on mine without issue and i would bet it will continue to be trouble free for 50k more! i am biased though ;D

steveespo's idea is basically what i did. but instead of making the disk and intake tract an inseparable assembly, the disk is bonded to the cap, so as to not permenantly alter the intake tube. the key is to eliminate the repeated flexing of the end of the cap along the inside edge. the sharp casting slag and flaws in the end of the intake tube will act like a saw or sandpaper on the soft rubber cap. the constant flexing action itself also weakens the rubber at the edge, causing it to fail.

I bought a 1 inch PVC plug and dremeled the top off to use as a cap inside the cooltech cap. What did you use to bond the cap inside the rubber cooltech cap?


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clear rtv. just make sure your disc is bigger than the opening in your intake tube. the rtv itself won't keep the disc from being sucked in.
pufferfish - i ended up using loctite plastic epoxy. The disc I made is 1 inch in diameter. It's not quite big enough to cover the entire intake outlet but it only leaves a tiny gap in one spot. It is definitely not small enough to get sucked in IMO.

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