OK, I saw this thread and did a search for the original mentioned. It is 22 pages long and had a ton of great info in it. There was many different ways that people went about this but I chose to take the route that cost me $25.00 at Lowes. I had to buy the extension and a new hole saw drill bit. I have the factory duel tips on the exhaust. It took longer to get each of them off and back on then it did to drill out and clean up the hole inside the muffler.
Here is what you will need. This list is detailed for the most novice of mechanical people.
*3/8 drive ratchet, shot extension, and a 13mm socket.

*3/8”electric drill. I used a 1/2” drill made for just this type of application. If you have cordless drill, be sure to have all the batteries charged as I read many people went through more then 1. But they did work.

*2” hole saw drill bit. I used this size but you can get a 2 1/8 in the exhaust w/ no problem. Some guys used smaller hole saws ( like a 1” ) and decided to go bigger after hearing the difference. I knew I wanted the biggest from the start. If you use a smaller size you can overlap the holes like a figure 8 to enlarge the hole w/out buying more hole saw drill bits.

*Allen wrench that fits the hole saw allen set screw for releasing the drill bit itself.

*Rubber Mallet.

*Extension cord

*Shop-Vac or an attachment hose on your house vac.

*Flash light.

*WD-40 or some other penetrating spray lubricant

*Gloves or good hand cleaner like GOOP. It’s the exhaust so it’s dirty!

Look at both tips and notice where the exhaust pipe is at inside it. I would do 1 side at a time if for no other reason you have the other tip to look at to make sure you get the 1st one back on in the right spot. You will want to put it back in the same place. Take off you exhaust tip w/ the 13mm socket/ratchet. These bolts are most likely rusted so spray them real good w/ the penetrating lubricant. Lefty loosie, righty tighty. You are upside down so it is backwards. If your not sure just apply some pressure 1 direction then the other to see if it gives. Be careful, these bolts get rusted if the car is drove much at all and you will twist the head off and need to get an easy out kit and a new bolt.
Use the rubber mallet to help remove the tip. You need to work it off and on by twisting it by hand and hitting it w/ the mallet.

( Pic #1 ) Get your drill bit extension and hole saw locked into the drill.

(Pic #2, #3 ) Start drilling. Every now and then ( for me it was about 20 seconds at a time ) pull the drill out and used the flash light to look into the exhaust to see progress.

( Pic #4 ) When you see the drill bit has made a hole stop and take the drill bit out so you don’t punch through the back wall of the outer shell of the exhaust.

 

( Pic #5 ) Here is where the Allen wrench goes to get the drill bit out of hole saw.

( Pic #6 ) You can see where I still got to the back outer wall of the exhaust. If the drill bit is still in you are likely to punch a hole in it that will have to be welded up. When you get close to having the hole completed just let up on the pressure trying to push it through.

( Pic #7, #8 ) This is what I drilled out of the muffler. You can see it is oblong and convex nature of going through the exhaust pipe at the radius. It gives you a bigger hole then the hole saw drill itself. Just make note if you want to start small. It only took about 2 minutes maybe less to drill it out.

Take the ShopVac and suck out all the little metal shavings. Replace the tip the way you took it off by twisting and hitting it w/ the mallet. It is going in at a slight angle and will feel a little funny. Then retighten the 13mm bolt and you are done w/ 1 side. It took me about 15 minutes on the first side. Just repeat the steps for the other side. Also, I would recheck the bolts on the tip after a few drives to make sure they are staying tight. If you want you can use a very small amount of the BLUE color locktight on them. DO NOT USE RED, they will not come off!

Have fun and enjoy the great new sound it will give you! In the original thread the dyno even showed a small HP gain. WIN/WIN!

 

Any power loss with this mod?

 

You can read through the linked thread and see the Dyno say you gain power. It isn't very much and only on the low end, but it is what it is.
You also get a way better sound out of the stock muffler for those not ready to dump out thousands of $ for a real system.

https://www.6speedonline.com/forums/...ler-996tt.html

I love the sound! I hated the stock sound of the car. The drone is gone and up till around 2500 rpms you have a good sports sound ( IMO ). After that it gets kinda quiet but none of the dreaded drone on my car.

 

Do you have any audio clips you can post or point to? I've been thinking about this, but the audio clips I've heard have not sounded too great.

 

I don't. Youtube jcbmemphis. Those are about as good as I have found. The last few pages of the thread linked above has some utube of a car going by at speed on the track that sounded pretty good to me.

If you don't like the stock sound and want a more growl/sports car sound then that is what you will get. No it is not as good as an aftermarket system! It is a temp fix for most that don't like the stock sound until they are ready to pay a few thousand for a real system.

 

I bet the sound is much better

 

It is... you will love it.

 

Big improvement IMHO over stock, but I wanted a better flowing exhaust so had been on the hunt months later. Just picked up a used Milltek Sport that gets installed in a few weeks.

 

We have modification that we do on the mufflers in a similar manner. We however cut the entire exhaust open, remove one pair of cats and modify the exhaust for more airflow. This creates an exhaust system which can support huge power(over 700rwhp) while limiting cabin noise and producing ZERO drone.

 

Zohair,

Tell us more about your modification? I had a similar mod done on my 993 with something called the RSR (named after it's inventor!) which had an excellent sound. It too opened up the original cans did some removal and then resealed the cans. The result was a nice deep sound with zero resonnance.

Do you have any photos of the internal modification or is this proprietary? Any sound clips? Any board references? What cost?

Thanks for the information.

K

 

As far as the TJW mod goes there is a big difference in noise. The cold start is much more rich and deeper. At warm idle the car sounds more throaty then the stock OEM. From stop to about 2500 RPMs the noise is a lot louder. It doesn’t bother me, it is a deeper tone but there is a vibration to the sound especially under load that wasn’t there w/ the OEM muffler. I was planning on pulling the rear seats and deck to add sound proofing in the spring anyway. At 2500 though the car goes real quiet and sounds real smooth. There does seem to be more response and the BAR for the 1st time went past 0.8 to 0.9 after the mod was preformed. Maybe it was just a coincidence?

If I don’t get a real system soon I’ll pull the OEM muffler and gut as much of the cats that I can. At that time I will take an extension/grinder bit and smooth out the edges of the holes I made in doing the TJW mod. Smooth air flow is always better and the edges have to create some turbulence. Maybe not enough to matter but it is a personal preference to have things as right as I can make them.

The real test will be if my wife likes it, she hasn’t rode in the car since the mod and I’m afraid she isn’t going to like the slow speed sound. But it will give her an idea of what I will have when I get a real system.

 

We have the system on one of our built cars, JustinN's BL850 equipped 996. On his car it is louder than what most will have as our turbo system is much more free flowing compared to a stock exhaust setup. I do not have any photos of the internal modification.

You can see a video of the car at the bottom of this link:
http://www.boostlogic.com/index.php?...tid=1:features

I will send you a PM for pricing information.