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Experimenting With Exhaust Discs

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I told some of the guys there I was experimenting with different size holes in the disc / baffles. He is what I came up with for today.

Update: As many know I have made many of these discs and still have them. Sizes are 1/2, 5/8, 3/4, 7/8 and 1 inch. One set shipped is $27 two or more just add $18 each, no extra shipping charges. Any questions please email me -- sjrsw (at)

With the 1/2 it sounds good and you can really here the motor. The 3/4 I really like a lot, good mix of exhaust sounds and motor sound. The 7/8 is starting to get back to no discs at all but still dialed back. I left the 7/8 for now because the 7/8 discs came out the best and I want to run it more to get a better feel. I had a friend help with these and it is the first time I heard the car from outside of it. I never realized how loud it really is with no discs in it.

In any case the 3/4 may be where I end up, as I said a real nice mix there. The vids are a bit rough, I did not do any editing and you may need to hear them a few times before you really hear a difference. If someone feels like putting them on Youtube, that is fine.

Also, this is running with pure gas, not E10 crap at 90 octane.








1 inch

Thanks Scott. I'll check them out next time I'm at my computer.
Here is the best of the no disc set


and another...lots of gurgle and pop ;D


Sounds and looks great!
It doesn't sound all that loud to me and that is the sweet signature sound- I would take them out permanently. ;D

Does someone have some inside info on what the decibel level is?
It really is pretty loud in person, I had no idea how loud until I stood by the side of the road as a friend passed with it. IMO too loud for driving around side streets. I have the 7/8 in now and I really like it. At first I was thinking too quiet but that is just inside. I found myself driving a little less agressive and it still makes good noise at higher RPM's. What it really cuts down on is the Jake Brake sound when you let off. It is still there but not overwhelming, I really don't want the Boss sounding like a truck.

Mark you should throw up a 3/4 and 7/8 video if you can.


How much trouble is to remove the disc? Do you have pics showing how to?
5 DOT 0 said:
I think it's three bolts on each side. The first side will take 20 minutes and the second 10 minutes.

Not even, just take out the rocker bolt and use a ratchet wrench to take off the two bolts where the side pipe connects to the main exhaust. Pop out the disc and replace what you want, takes two minutes - three including jacking up the car. It is pretty easy :)

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