I would think that the hollowed cat would be louder, and the high flow cat would be a bit quiter and flow good.

I would just get a magnaflow cat.

 

Hmm. Never really noticed the difference. But that was because my car had a different engine displacement (2.8 vs 3.1) when it had the test pipe (ILLEGAL in most smog police states if not ALL, thanks to the PO of my car) welded in place of the cat and its flanges. Besides that, both the 2.8 and 3.1 were badly misfiring due to bad fuel injection for about 80% of the time I had my Flowmaster (improperly installed, that PO again... cutting that thing out was F U N!!!). Never really got to tell the difference. Not even when my original replacement cat ended up hollowed out.

And yes, to get things the way they were supposed to be to pass inspection (visual REQUIRES a cat in place or something that looks like it) I had to replace EVERY pipe from front to back (have you ever tried to fix the crossover pipe, which is a pipe inside a pipe, when it is broken right where the pass side down pipe connects to the rest? I have... ), install a new cat, and find a way to not get the whole mess to keep dropping towards the ground (locking nuts) because I didn't have a trans hanger of any sort, and still don't.

 

sounds tuff. Hey how do people hollow out there cat ?

not that I'm thinking of doing it lol....

 

Set it up over a bucket or something, and ram a steel pipe or rod down in there and break the honeycombs up. Just don't breathe in the dust that comes out. It's really nasty stuff.

 

Thanks man...

 

Okay, so I finally went and recorded some sound; sorry it took so long (only eh, 2 months :] )


Nah, I left the cat how it was - even though it probably has some imprints of speed bumps in it :| I guess I'll do that sometime.

Still a stock 3.1; oh and I finally did a tune up (oil, plugs, wires, etc).

The first file is right after a cold start;
and the second one is after I drove it down the road a bit.
On the second one, when I rev it and leave it in high rpm's it's at
about 3k-3.5k, then the little rev on the end of that goes to about 4-4.5.

 

I like man....I like....


Thanks for adding the clip

 

The PO installed a "SoundFX" muffler on this 2.8L 84 firebird here.
**original removed in favor of youtube** http://www.youtube.com/watch?v=rap2PKN4e1U
From early this month that was recorded a little while after starting with a temp of 5C(41F) outside.
It has an unmolested cat on it. No other aftermarket stuff added in however the current setup could use a trim at least. ...perhaps so the ends do not stick out the back so far...

I know it is not a flowmaster or magnaflow but I am linking to it anyway just so this thread has a wider range of muffler clips.

 

man you have to go threw some stuff just to hear it lol...

you should try putting it on youtube...

But sounds good....

 

http://www.youtube.com/watch?v=rap2PKN4e1U
There, on youtube.

 

i have magnaflow on my 3.4l grand am and i love it. i wouldnt thing there would be much of a difference in sound. but i dont know

 

Thats not bad and if you trim the ends back and add 4in tips it would sound better .

 

Hey thanks for putting it on youtube...a lot better for us to view and hear. I like the way it sounds at idle, sounds like a v8 bird is right, try it out...hear his clip...sounds good.

Either way I like man, now to kill the raspy sound....

 

you should try to get a sound clip of it. . . There is no clip of a 3.4...Now I'm curious on how it sounds. Magnaflow....yup you can hear the difference.


Let us know when you get that clip if you can...

 

I used to have a '95 olds ninety-eight. It had a 3.8L supercharged engine...

I replaced the converter and resonator with a gp and put on a 2 1/4" thrush welded muffler... sounded great, especially once I ran 3" tubing after the muffler. Got pulled over the day after I put that tip on actually because it was loud, but since we don't have emissions testing here in MI, the cop couldn't do much of anything. I told him that I just put in a high flow muffler and 3" tip and he let me go.

I actually am a co-op at an exhaust manufacturing company who makes dynomax, thrush, and walker. At first I had just a straight pipe in place of the converter and resonator, but had a very bad popping sound at high rpms. I asked my boss about it, and he told me that there was a "standing wave" which was creating the popping noise... The resonator helps to collide sound waves together in order to silence them, just like in a muffler. I suggest that if you are removing the CAT and resonator, you put in a GP. This fixed my problem, but removing the converter usually causes a raspy sound... I personally don't mind it too much. You might be alright with just a resonator though, not positive.

 

heres a clip of my 85 2.8 befor it was turbo, i had the stock downpipe, removed the cat(just replaced it with a straight piece of 2.5 inch pipe and the muffler is a "Ractive" i though it sounded pretty cool..
http://www.youtube.com/watch?v=yy-yYTHuOhM If u just want to here the sound of the muffler start at 5:00 minutes the rest is just the joy of beating on a 2.8 haha

 

I'm gonna make another video when i get off today. i changed a few things and my tech that does some of the work for me told me it sounds more mean and runs alot better lol. I just changed like the o2 sensor and intake, just small stuff but it helped. I've got a magnaflow cat and a flow, not sure what series it is but I like the sound. I've got turn downs on mine cause i never found a set of tips that i liked that wouldn t make it look like every other camaro.

 

http://www.youtube.com/watch?v=r6iw_kULmB8
ok guys there it is, I just made this. Tell me if you like it or not.

 

Lmao you dogged the hell out of that car!

 

LOL ya he did...

 

That was a good video.

Sadly i will never see what my EX Firebird could or would do

 

Ok after checking out all the clips on here does anyone here have a clip of there v6 with headers and an after market exhaust....?


I know theres headers out there....


Thanks guys...

 

... I would also like to know as I'm looking into buying headers... It's either going to be the front half getting replaced or everything behind the cat, one of the 2.

BTW, where did you guys find Magnaflows for less than $300? That Dynomax is very tempting right now.

 

I was giving that price at a exhaust shop. I asked what it would cost to install a magnaflow exhaust with 3 inch tips. . . they gave me there price and I gave them the go ahead....

Let me know if you find anything on the headers....

Thanks mav

 

I want the Pacesetter headers for mine .

 

Hey you going to put that clips of your bird going up hill? Gotta hear it man...

 

I would have to do it again and make a clip but Blue is a little under the weather at the moment .

 

So guys, after doing a search of the V6 section and some reading; it is in fact correct that the following (see attached image, I do not know the specs or a model number) from a parts truck here would sound pretty bad on a 2.8L V6 in a Firebird with stock cat?
Right?
The only reason I even consider verifying this is because the existing clips around are not really all that great wrt the sound quality(*shakes fist at cell phone cameras&mics*) and it seems that someone has always knocked out their cat or replaced it or other crap like that.

I just have to check and be 100% sure because this red sucker here is available, most likely free and is a fair bit smaller than the current muffler on the 'Bird.

 

That looks like my Thrush Turbo 24201 2.25" x 21" muffler... My sound clip DOES have the stock cat, but the engine was rich at that time and is worse now (MAF keeps getting worse and worse as time goes on). It won't sound too bad as long as you get some decent outlet pipes.

 

Do you have an updated link to that? When I click on the link you posted on page 3 I get a blank page titled "Untitled Page". Used the search feature on cardomain with your nickname in it but got nothing. I guess you have a different nick there. :P

web.archive.org (the wayback machine) has been prevented from indexing it as well so I cannot get information to use while searching there either.
http://web.archive.org/web/*/http://...BFB3043FA7C8C2

:/

 

Sorry. They apparently changed their video system and my video got deleted. I've replaced it now. BTW, my S/N over there is martianent. It's going to be a bit before their system has it ready, I suppose.

http://video.cardomain.com/VideoPlayer.aspx?id=734429

 

Thanks for the new link.

 

Good eye man...

 

Running the Cat. should help keep the popping down from that Glasspack also .

 

Well, it was either a Thrush, a Cherry Bomb, or a Red Hottie (yes, that is a real name, I believe Edelbrock or someone makes it).

 

Ok, I talked to someone that was present when the truck with the glasspack was purchased and he seems to recall the PO saying it was a cherrybomb.
So I pulled it from the truck(it is a parts truck*) and prepped for a short video.
Here we start off with the Walker SoundFX then that got pulled off and another recording done with no muffler; after that the glasspack.

http://www.youtube.com/watch?v=LxO8v0zJhls

The camera does wussyHD 1280x720 video(that is what you call 720p(1080p is 1920x1080 for those who do not know)) but is pretty shitty quality. The mic in the camera is not very good either and right behind the car like that it gets raped by the noise so I had an external one connected to my laptop and used that to record the audio. Once done got it all synced up and everything trimmed and ready for upload to post here.
Unfortunately even my external mic was not suitable for the lack of a muffler. hehe :P



So far I think I like the walker more than the cherrybomb since it is less farty sounding to me. Unfortunately that means I now have to pull the glasspack off and put the one that the car had to begin with back on. >_<
Oh yea, and it turns out that this car does in fact not have a cat. I could have sworn I saw one on the Y pipe the PO pulled from a spare S-10 engine but I guess I was mistaken. I also feel like a moron for not just looking under that side of the car to confirm..


*This parts truck is an 89 F150 and is basically mine to take whatever I want from. Too bad taking the 5.0L engine from it and sticking it in the 'Bird would be a ton of work. :S A 5.0L might be nice in the Firebird. The glasspack sounded badass on that truck too.

 

wow... That just sounds awful, no matter what muffler is on there. Im sorry, but that high pitched buzz, what is that?

 

Most certainly does.

It's a V6 baby!
hehe

More seriously, you can hear other v6 cars in this thread buzz when they let off the throttle as well... they just seem to drop the RPM faster.. so you do not notice it as much I suppose. As to why they rev up and down faster I dunno. Either there is something wrong with this engine(entirely probably)(aside from it being a V6) or most people only rev lower or something. I am not sure and I cannot remember all the RPM ranges people have said they hit in their clips so I cannot say for sure. *shrug*

This engine was quite abused by the second last owner so it probably is just about ready to puke it's guts out anyway.

 

My 3.1 stock only minus the cat and it doen't make that sound at any time :/

 

*shrug* As far as I can recall this car has always sounded like that for as long as I have known it even with the very little remnants of the completely rusted out stock exhaust still barely attached.

As far as I can recall anyway.

 

That video sounds pretty close to every 2.8, 3.1, and 3.4 I've ever heard without cats. That includes about a dozen Fiero's, and the same number of Camaro/Firebirds. The best thing you can do to make a 2.8-3.4 not sound like garbage is to leave the cat alone, or make sure everything is sealed air tight and install a quiet (stock parts store replacement) muffler. Flowmasters probably sound the absolute worst with a gutted cat.

 

I have a 2002 WS6 catback on my 2.8 car. yes overkill, but it was sitting around the shop, and it looks good. Sounds...I can not say much for it still being a 2.8.

 

I'm gonna get my car goin tomorrow and make a cell phone video of it.

 

Best muffler? No muffler (and a glass pack).
http://www.youtube.com/watch?v=3DBuIAcbVDw
What, you can't embed videos from YouTube?

 

My Hooker Supercomp kit came the other day, i should have clips of it with the longtubes in the next month or so. Just need to get the headers coated and the engine back together...

 

Stock muffler is the best muffler. If the car was supposed to have something else, the engineers that get paid millions of dollars to design these cars would have put that in.

 

Except for the fast that often the beancounter say meas more than the designers. Or the fact that automakes will often make cars very mild to appeal to a more broad customer base.
By your logic, no cars should ever be modified because the millionare engineers already designed the best product and it came stock...

 

Has anyone found headers that we can buy for the 3.1L? I have a 91 Firebird Vert that needs an exhaust manifold. If I can find some headers I will replace manifolds. Anyone????

 

The Pacesetters headers for the 2.8 fit. Fit the 3.4 as well. Same motor, different stroke/bore.

Painted: http://www.summitracing.com/parts/PSM-70-1206/
Ceramic: http://www.summitracing.com/parts/PSM-72C1206/

Oh, and I'll post a new clip of my Camaro with the stock exhaust (previous clip was with bad fuel pump).

 

It's in need of a tune up, but after I replaced the fuel pump a few months ago, it's had a more aggressive idle. The buzz is a typical GM V6 sound. My dad's Grand Prix does the same sound.

Here's the clip with stock muffler/exhaust, engine warm, and 5,000rpm rev:

http://www.flickr.com/photos/25961017@N05/4683254110/