posted                      

quote:

---

The 97 Camaro SS - "Cone of Silence"
All Photo's Taken of My Camaro SS #1341 (Valkyrie) on January 20th 1998.


During a recent discussion on the Camaro SS Mailing list it was discovered that some Camaro SS's built during 1996 and 1997 had been "quieted."
After some research it was reported to the list that early in the 1997 model production year the Camaro SS failed a drive by test which required the cars to "quieted" down.
Now as many of you know April 1st 1997 SLP redid the "Performance Exhaust" option. The newer exhaust had to meet more stringent noise limits. This was done by splitting the exhaust so that it now had exhaust tips on either side of the vehicle.


However, before this new exhaust went into effect in April it seems that SLP (At Chevrolet's behest) inserted a restrictor into the exhaust pipe to quiet the cars down even more. This device which we have been jokingly calling the "Cone of Silence" after the old "Get Smart" television show further restricted the exhaust."


Details on "The Cones" Removal

After hearing about this I took my car to the local Meineke outlet (#588) in Palos Heights, Illinois. The owner of the shop Brian Lawrence is a performance enthusiast who has worked on many F-Body vehicles (including his own Z/28). He has over fifteen years experience in the field. He along with manager of the shop John Cozzi who has been doing this for over eight years, listened to the problem, and said it should be a simple fix. Brian also was quite willing to discuss other perfomance exhaust systems his shop handles. For those of you near the Chicagoland area this shop is worth looking into. Give them a call at 708-448-0632.
As a side note they also noticed a leak in my rear pinion gear while the car was up on the rack - so it's back to the shop for the Valkyrie next week.


My car has been driven 14,500 miles since I got it last January 4th. The stainless was discolored as you can see from the pictures. John was able to quickly remove the brackets holding the pipe to the "over axle" pipe. Unfortunately, no amount of heat would allow the pipe to be separated because there simply was not enough room to turn the pipe and hitting it was almost out of the question since the floor was so close.
Brian suggested that the muffler be removed to allow them more freedom of room to work. I immediately agreed. Another note here. Brian was nice enough to wave the regs and let me into the shop to shoot these photographs. He also waived the cost of the job. This was a very nice gesture on his part and was greatly appreciated.


Once the hanger and clamps were removed and the pipes were heated the joint from the "over axle" pipe came away from the muffler and there it was "The Cone of Silence." It seems that on some installs it was easier for SLP to insert it right next to the muffler. As a suggestion I would recommend most people start here because it's a lot easier than taking apart the other connection, especially if you have several thousand miles on you car as I did.


As you can see from the balance of the pictures this little metal cone restricted the exhaust in my vehicle from 3 inches down to less than 2 inches. In other words I had less interior diameter than a stock Geo Metra. (See photo with tape measure.) The entire job from start to finish was less than an hour and should cost less than $30 at most muffler shops. My car was dynoed last February and is due again this February. (Kind of like a once a year baby photo.) It will be interesting to see how much of a performance gain this was worth. I only wish that I had dynoed it before doing this and then immediately afterwards.


For what it's worth my car is #1341 and was built on Thursday, December 19th 1996. This means that if your number is higher than mine and you were built after December you definitely have it. Geno I owe you a donut!"


Hope this helps all of you guy's with "performance exhaust" out there. I did notice an immediate increase in the volume when I jumped on it. Unfortunately, the snow is once again starting to fall here in Illinois so it's back into the garage for the Valkyrie.


Description of Photos

Photo 1 - This is a picture of the cone next to my removed muffler

Photo 2 - This is what we found when the muffler was removed. That is the cone protruding from the pipe.

Photo 3 - Here John Cozzi is applying the torch to loosen the muffler from the pipe.

Photo 4 - As you can see from the ruler the actual diameter is 1 7/8.

Photo 5 - This is a another shot of the muffler and cone together.

Photo 6 - Picture of my cars "Performance Exhaust"

Photo 7 - Another comparison shot

Photo 8 - Shot of John heating the "over Axle" pipe.

Photo 9 - Shot of the pipe connect with the heavy duty clamps.

Photo 10 -Shot of the cone mounted as a hood ornament.




Who has had it?

Earliest Cone so Far ----> Brad LeMay 97 SS #58 (Built 8/96)


This problem has been reported on several Pontiac Comp T/A's

---

posted                      

quote:

---

Originally posted by 30AnnySS:
...but if it comes apart easily, i'm gonna remove it...

---

Take it to a muffler shop and have it removed today! You won't believe how much a difference it'll make. As it currently stands, your Performance Exhaust option is worthless and is more restrictive than the stock exhaust. I had mine removed the first week of ownership...

posted                      

quote:

---

Originally posted by 30AnnySS:
...How did you guys remove the cone? There was NO way mine was pulling out, so we cut it off flush with the main pipe...I really didn't notice much, if any change in the sound of the car...

---

Mine had to be cut off flush with the main pipe as well, it wouldn't budge. As for the sound, it's not much of a change but the air flow, which equals power, is much better. Now...you're getting the benefits of the Performance Exhaust option.

Disconnect your battery for a while and then reconnect it for instant power gain. Otherwise, it'll take the computer a few days to adjust to the new exhaust flow.