Ok, so I like the sound of the ti exhaust of the Z06, but I want something louder. Seeing as this is my first Vette, I was surprised at how much $$ exhaust systems, catbacks, even mufflers are for this car. So I started looking for viable alternatives. I knew that I would be fabbing up something myself and installing it on the car to keep it cheap.

The first idea I looked at was the bypass mod on the ti’s. I think that would sound good and be easy, but I don’t have the stuff to do it and don’t know if any of the muffler shops close to me have even heard of titanium exhaust pipe. Besides I don’t want to pay a shop for something I could do myself with some effort and my crude set of rudimentary tools.

The next idea I looked at and listened (online) to was straight pipes after the factory cats and midpipe. I thought with stock catbacks easy to find and cheap I could cut one up and add some pipes and be done. This looked easy enough to do for a diy’er like me but I didn’t think I would like the sound., especially the popping on deceleration or when you rev the engine.

Then I saw a couple of threads on modifying the stock C5 (non ti) mufflers. After seeing the pics of a stock muffler opened up I knew exactly what I wanted to do. Credit to pkmoose ( http://forums.corvetteforum.com/c5-t...-mufflers.html )for these pics:





If you look close you can see there’s a gap in the inlet pipe in the small center chamber of the muffler and the another small section of pipe that directs flow into the rear of the muffler where it has nowhere to go.

Looks to me like this muffler would create a fair amount of backpressure (as well as sound reduction).

After reading a thread where the guy opened up the stock muffler from the top and cut off all the pipes flush with the inlet: http://forums.corvetteforum.com/c5-g...ing-out-2.html


Well I knew I wouldn’t like the tin can raspy sound so I came up with an idea to open up the stock mufflers and retain some of their muffling but let them flow better and hopefully sound better and louder.

Here’s my idea - cut out most of the far baffle to expose the outlet pipes to direct pressure from the exhaust bouncing off of the rear of the muffler.



Hopefully this will prevent the raspiness and cut down on the popping. My thinking is that by allowing the exhaust to travel all the way thru the muffler and leaving the inlet and outlet pipes the way they are it will still be like having full use of the muffler. Kind of like a “chambered” muffler (I hope).

So I found a stock uncut set of axle back pipes and mufflers locally on Craigslist for $30:



I cut off the end cap of the stock mufflers:



Here’s what it looks like from the end:



Here’s what I cut out with a drill, sawzall, and dremel:



Then weld the cap back on (I have a flux core wire welder so it is hard to weld sheet metal for me that’s why no close ups of the welds) Took a while and a couple of passes but I got it on and sealed up, ground down and primered with high heat primer:



After the primer dried I painted the welded area with high heat bbq paint to prevent rust:



Now they are ready to go on the car. I’m waiting on some jack pads I ordered to get here and then time off work to do the swap. My plan is to swap the catback in the garage on jackstands. I’ve seen threads where others have done it so I believe I can do it too. I’ll post some clips after I get these installed but I’m not sure when that will be. Just wanted to post up my idea on modding the stock exhaust for any budget minded modders out there. Thoughts?

 

Can't wait to hear these.

 

+1

I'm not looking for extra horses just a great sound. I've not heard any aftermarket systems that have a nice low muscle-car sound. They all sound raspy. And the majority are WAY to quite at idle (I need to keep the cats). And to pay $500 and up for is not in the cards for me.
Looking forward to your results!

 

I agree 100%. I have to have cats too. I figure I can do the bypass mod on these too If I'm not happy with the sound and I'm only out $30, some welding wire and my time.

 

Good luck swapping them out on jackstands. You have to get the rear of the car REALLY high to be able to swing the tips down far enough to loop the front over the axles. I always end up dropping the cradle when I do stock catbacks. This is the reason you see so many of them cut in half when shops install aftermarket systems.

I'm excited to hear these though. I like the stealth aspect of keeping the tips stock. Anyone who knows anything about corvettes wouldn't think twice about a car with stock mufflers....


Jack

 

You must have looked for like 1 minute with the monitor turned off. There are plenty.

My SLP power-flo are quite the opposite of raspy. They rumble, growl, and roar. I tried Corsa and hated them. There are others of course that aren't raspy...GHL bullets, borla, etc. maybe the stock manifolds are hindering you.

Regardless, good job on the mod! Looks good.

 

I have no doubt that there are some aftermarket exhausts that sound good. I just can't afford them right now. Based on my goals for this car I'm gonna end up with lt headers, x-pipe w/ high flow cats and the stock Z06 ti system. It should sound how I want with the headers and x-pipe then. But for now I just want more sound without the crappy popping or raspy tin can effects.

 

A quick search yeilded these 2 clips
http://www.youtube.com/watch?v=A85r-dnq-E8
http://www.youtube.com/watch?v=hjg_mzTTujU

The second one sounded better (to me) and louder at idle.
They both had the raspy sound at revs.
Heard other clips as well but the raspyness is still there. Perhaps the stock manifolds are the issue - don't know. I've also heard that you'll never get the old muscle car sound in the new motors because they are just that much different (firing order was mentioned). Don't know if that's true or not but it does make sense. When a late model Mustang goes by, you don't have to see it - you can tell by the exhast note what it is. I was hoping to just add a Cherry Bomb and be done with it! But apparantly you can't do that!

 

Looking at the way the pipe necks down inside there, along with the horrible flow path when stock, there is no way these don't restrict power on anything other than a stock engine with manifolds and stock cats.
Even your mod still leaves the potatoe in the pipe.
I wonder what the TI muffs look like inside.

LS motors sound different due to the firing order. Add an X right after the collectors, and the sound becomes completely different.

When I bought my car it had this along with the stock manifolds, cats and Borla stingers.



The sound was nice and mellow. Not at all raspy. and because the was back a ways, it didn't have an X sound. If you lived in Oregon, you could come and get it for free. Made by Magnaflow.

Ron

 

It would be great if this works and sounds good. There are a lot of us with almost new OEM exhaust systems in storage that we could sell.

 

That's part of what drew me to do this. The stock catbacks are not hard to find and usually can be had very cheap. Although i saw one on ebay for like $600!!! I guess the the guy thinks because it came off a Corvette and is in good condition it is rare and valuable.

 

Yeah I was amazed when I saw the inside of these. No wonder they are quiet, and I agree they are a huge restriction. I did leave a lot of the internals in place but if you look carefully there's a small gap between the inlet pipe and it's little extension pipe that goes almost all the way to the back of the muffler. Now the 2 smaller outlet pipes are exposed to almost direct exhaust flow and they go straight out from the point you see them. Should open it up a lot.

 

You should hear something in person instead of trusting sound clips from online...I'd be offended if anyone said mine sounded raspy! No lie, I've had a die hard mustang guy ask me what exhaust I had cause he was jealous of the sound.

 

That's probably why there are so many threads on exhaust sound!
Too bad I don't know anyone who has the SLP power-flo installed. However... it still doesn't fit into the low-cost effort that the OP is trying!

 

I wont change the uniqueness of the stock Ti units so I plan on the Bypass mod sometime. But I hate the stock single wall cheap looking tips. My old M3 has a AA Gen 3 exhaust with beautiful dual walled stainless tips. Not seen any threads on welding on new tips in here.

 

Ok I got these on yesterday.
Couple of observations:
1. I am amazed how LIGHT the ti system is. I will be putting that back on in the future with longtubes & x w/ hi flo cats. (It would be really sweet to have a titanium x pipe w/ ti cats!)

2. These mod muffs sound almost exactly like the ti system from inside the car, only slightly louder. (I will probably do the bypass mod on these seeing as it will be easier and I don’t have the stuff to do the ti’s)

3. They aren’t that loud outside the car. Best part is no popping when you let off the gas!

4. I guess I am not used to the exhaust note of the LS series of engines. Seems like finding the sweet spot in sound is difficult.

5. For those who haven’t and are planning to swap your catback yourself: You must have a minimum of 30” from the ground to the bottom of the exhaust tips to get it off without cutting. I had 27 ½” to start with and it wasn’t enough.
On the same note it was a little nerve racking to get the car up that high, but once it was up there doing the work was not bad at all. (My neighbor thought I was crazy) I have been working on my own cars for 27 years so I know to be VERY careful jacking/supporting vehicles before working on them.
All in all it took me 1 hr. and 45 min. start to finish and that’s with having to stop and jack the car up more.

So I tried to take a couple of cell phone vids but the audio is really crappy. In person the exhaust sounds VERY good. Remarkably similar to the ti system - maybe slightly louder.

Idle/Rev:


Drive By:

 

My bypass for comparison...

 

That's just the bypass without messing with the stock mufflers?

 

Good job on the mod! I've gutted mufflers on different cars in the past when there were no aftermarket systems easily available. Your car looks great too!

 

Yes...biggest pipe that could be fit as bypass. I like it for the bang for the buck Sounds nasty at WOT. Had a shootout with a Corsa Indy. Side to side from back....the Indy is a touch louder but sound the reviewers and I felt similar "tone".