So I went to my mechanic and asked what could I do to improve my cars performance (Im a newbie). He said add a header. So I went to the guy he recommended and he said a header meant not only to put a new header but also bigger piping in order for it to work correctly. But he recommended me just to change the pipping and he said I would get almost exactly the same result doing just that than spending more in adding the header. So he said it would cost 300 dls (im in Mexico so Im converting the currency) and that if I wanted a header it would be the 300 for the piping plus the header (around 400 for just the header)... so he recommended not spending those extra 400.

Finally I got my car today, and I really liked the exhaust tips lol and I noticed improvement but it is TOO DAMN NOISY for me, specially since it is my daily drive. I asked him what I could do about the noise if I could add a silencer or something, and he said it was possible but it would go against the performance I just gained because this will reduce the "free path for the gases" and decrease their velocity or something like that. Its really difficult for me to explain since I dont know the correct english terms.

The mods he did were:

change all the 2" pipping for 2" 1/4, add a "bullet silencer" (I just directly translated from spanish "bala" to english...) and I also told him I wanted a dual exhaust so he added a "Y tube" and put my 2 exhaust tips (80 dlls for this mods to have a dual exhaust)

here is a pic about the exhaust tips, I am still wondering how to take a pic of the actual pipping under the car so u can see it...



Any suggestions on how to reduce the noise????? If u want I can add a sound recording or a video so u can hear it. Was I charged too much?? I am starting to think I threw almost 400 dlls to the drain... and since Im still a student that is quite a lot of money for me...

I appreciate any comments.null

Anyone driving slower than you is an idiot, and anyone going faster than you is a maniac...

Just add a resonator after the cat converter.
Assuming you still have a cat on the car.

-M


Remember....syringes go in the RED waste basket.

I think I still fot the cat converter if not I will be pissed...

Will the resonator deacrease "performance"? any idea on price?

Thanks!


Anyone driving slower than you is an idiot, and anyone going faster than you is a maniac...

At least the guys at these shops are being honest with you. Everything they've told you so far is true but you could get away with adding a straight through resonator and not lose much in the performance area.



I used to race cars, now I race myself.
5K PB: 24:50
10K PB: 54:26

Those are good looking tips



now The L61 Powered Fiero
PURE DICE, PURE Design.Innovation.Creation.Excellence.

Just pick a glass-pack muffler of the same inside diameter has your extention pipe ('Cause that's what it'll be goin' in place of!) that has it's louvers punched from the center of the pipe outward into the packing. It's flow just like the extention pipe & take the raspiness outta your exhaust note, giving you a deep, mellow tone & a lower noise level. Which everyone will appreciate, cause fart-cans suck, and even small-engine builders hate them.

And why didn't you have a conventional muffler installed? Glass-packs alone aren't enough to really silence the noise. You need a "turbo-style" muffler installed, the way the factory did, to get the noise down. Then add the glasspack in-line between the catalytic convertor & the first bend before the rear axle that leads to the muffler mounted in the factory location.

As for your choice (Insistance?) for the dual-tips, that the thing that really makes your system so loud. You now have to much inside (The pipe) area for the exhaust to flow through, and now it's resonating off the inside of those pipes like you're driving under an overpass. And you know how that sounds, right? Heck... Why did you even change the exhaust system in the first place? Did you mod the engine from stock in a way to make it produce more power than the stock system was designed for? No? Then why did you waste money on this slip-shod system? You need to learn how & when to make such changes, and I think I'll need to be the one to teach you. Let's start at the very begining...

The rule of thumb for exhaust building is for it to flow 2.2cfm@10.5" vacuum-drop for every HP the engine produces. Now, first you nedd a resonable estimate of what your engine's peak HP is. If the engine is stock, the number listed in the book shall be your guide. And don't count those short-ram open-element air cleaners that open-up under the hood without any shrouding or help to collect outside air, as they really don't do anything. If you haven't done anything serious to increase the engine's breathing (Increased displacement, bigger cams, header, port work) you don't need a new exhaust. In fact, only a few minor changes at most may be needed if you haven't done the things I listed.

If you really want to improve on what you have for exhaust, and want to keep the dual tips, but don't want to get too deep into the technical of how you should, I suggest you install a glass-pack like I said to, keep all the other pipes involved the stock size, find a dual-outlet replacement muffler for a 3rd-gen Camaro/Firebird or Buick GN and have that installed in the factory muffler position, and have the outlet pipes from it being of a combined area equal to that of the stock system's. Here's the math to figure out what that is: dia. x dia. x pi. Divide that by 2 and you'll have the needed area of the tailpipe extentions needed to match what your car needs to be quiet but not choking with dual tips. Then you can have your tips attached. You'll need to go through the numbers on a few different sizes to find the one that comes as close as possible to being the same as stock (But not less!), but it'll be worth it in the end. And if your "Mechanic" says other wise, tell him to stick to just swapping parts & go find another.

Oh yeah, and those tips (From the looks of them) are acting like megaphones, which amplify the sound of whatever passes through them. Change them for some straight tips or resonator-style tips & that will help too.


Go beyond the "bolt-on".

First of all, thanks everyone for your comments. I also want to clarify some points


I just checked and I DO have a Glasspack. Im not sure I have the catalytic converter though, how can I check? I will go to the shop and ask them to show me exactly what I have, what they took out etc. and post pics. As far as I saw right now, I got a long glass pack, 2.25 in pipping and then my dual tips. There is no box before the tips like I had before, I believe this is called silencer right?

I read somplace that if the glasspack is installed backwards then this will not reduce the noise but increase it right? Maybe the guy screwed up and installed it backwards? because he said the "bullet as called in spanish" what I believe is the glasspack u mention as I look for a pic on ebay, was to reduce the noise. He asked me if I wanted camaro style tips, but I didnt really liked how they looked. Would that have been less loud? Finally, Im really cocnerned about price in order to decide if I can trust this guy or not. Glasspack + 2.25in piping + 2 dual exhaust tips for 380 aprox is a good price or not?


Thanks again and yes Im constantly screwing things lol but I guess thats a price Ill have to pay for learning.







Anyone driving slower than you is an idiot, and anyone going faster than you is a maniac...

A catalytic convertor is usually found relatively close to the engine, in your case just after the flex-tube. It's a two-piece clamshell of stamped steel with a pipe seeming to run between them. If it's not there on the year your car is, and you didn't have any steps taken to "fool" the after-cat exhaust gas oxygen content sensor, your car's on-board computer would turn-on the "Service Engine Soon" light. So I'll say it's there, since I can't see for myself.

Yes, that "box" is the "silencer", as you called it. Funny term that is... It's what "mufflers" were called before the word muffler was applied to them. Before that, a muffler was a fur-piece that women wrapped their hands inside of & carried in front of themselves on cold winter days. But enough of that... You say the muffler was eliminated? Bad move! No wonder the system is so loud... Your mechanic just removed the most critical part in exhaust noise reduction! Just a glasspack muffler will do little to reduce noise. In fact, it's the noisiest design of muffler made! Ever hear the 'supposed" sound of a hot rod on TV? Or in anime? That's what it sounds like with a V-8. So you can imagine how bad it sounds with a 4-cyl. But then, you already know that... Don't you?

As for it being installed backwards, it possible... If it's a design where the louvers (Remember how I mentioned them earlier?) are punched inward, towards the center of the tube. Those louvers are set to "capture" the exhaust pulses & direct them into the packing. They're meant to face into the flow of the exhaust stream. If it's installed backwards, the silencing effect is negated. And you know what that means. Although, there is a different design of glasspack where the louvers are punched outward (Remember how I mentioned this?) that'll do it's job no matter which way it's mounted, but this design doesn't do as good as job in silencing. But it does flow better than the other design would, regardless how the other may be mounted. And the term "Bullet-style muffler" is just another name for glasspack. It's just applied because the case of it has a bullet-like shape. By the way, is the glasspack you had installed red in color? If so, then it's a Cherrybomb glasspack, and it is possible to install it backwards.

What I mentioned earlier was using a Camaro "silencer", not Camaro tips. Using a 3rd-gen Camaro muffler (Namely, one for a V-8 model) will allow you to do the dual-tip thing you're after, but it must be installed where, and how, the old muffler was. And what you have is two double-style exhaust tips, not two dual exhaust tips. But once the Camaro muffler I mentioned is installed, you can have whatever design of tips you like... In dual fashion.

And finally... Yes, I wouldn't trust that mechanic you have. He obviously don't know what he's doing, and talked you into installing a exhaust that will get you a police fining ticket for sure.

Just install the following: A glasspack "silencer" just after the catalytic convertor, a V-8 '82-'92 Camaro muffler, and then whatever tips you want on the ends of the tailpipes. And keep the rest of the system the same size as stock, unless there's been a serious change in how much power the engine makes. A reputable exhaust shop should be able to do it for you.

That's all & good luck!





Go beyond the "bolt-on".

(SIgh) I just read your PM, and no... Adding two more glasspacks just before the tips is not the way to go, since it really won't lower the noise level that much. Look... If you really want to see how to built a quiet dual-tips system, just look around here (Search) & see what others have done. You'll find that they did the same thing as I told you to, again & again. Heck, some of them have pictures of their work that you can print-up to show your mechanic what to do.


Go beyond the "bolt-on".

Have you thought about getting some Dynamat instead?
You can install dynamat in the trunk of your car and see if that helps.

Also, I might have read into this wrong, but the mechanic saying getting the header and exhaust is a waste compared to having just an exhaust does not sound correct at all.

The exhaust should be the first step, perhaps this is what he meant?

I know an exhaust with a header is going to perform better than just an exhaust alone.



2003 Sunfire with 2 1/4 inch turbo muffler, 2 1/4 piping, 2 1/2 inch resonator, a 2 1/4 inch catalytic converter, 2 1/2 inch down-pipe, a 4:2:1 RK Sports 'clone' header, E-bay strut brace, ground wire kit and an AEM true cold air intake NOPI edition.

^I agree. A header will do more to make power than just a custom exhaust would, especially on a otherwise stock 4-cyl engine. Also, it's best to get the exhaust at least set-up first before buying a header, since it may be awhile before you have the money for a header. Take a good look around here to learn what others have done, then have yours built. And stay away from Mr. Badwrench (Your "mechanic")!


Go beyond the "bolt-on".

Well, on Monday I got my problem "fixed" ($100) I got two glasspacks one before each tip and the noise was considerably reduced. I think I have been using the wrong term. The problem was not the noise or the "tone" of the sound from the exhaust, the problem was the "volume" of this noise, it was too damn loud. With the two glasspacks the tone is even better than before and the volume is lower and comfortable. Maybe this is not the best solution but I dont have enough money to get everything back to stock.

About the header, there is a guy that sells headers for the sunfire on ebay Mexico for 140 dollars and then a reputable shop here in my city sells it for $240 for a black header or $390 for a polished looking one. What are the things I have to check in order to decide which one to buy? Do you think this are too cheap and will be broken in a couple months? Are there any negative effects on puting a header in my car?

Thanks for your replies!


Anyone driving slower than you is an idiot, and anyone going faster than you is a maniac...

No real negative effects, just may need to adjust the fuel trim a bit after it's installed to make the most of it.

As for what to look for:

304-Stainless steel

3/8" flanges

Ceramic Thermal-coating

14-gauge tubing

If you sources can't at least meet the two in the middle, don't bother with them. The flange thickness effects sealing ability strength, and the ceramic thermal-coating effects durability greatly on a street-driven car. The first & last are quite critical, as they effect durability & lifespan. Stainless-steel won't rust like mild steel would (even if it got the ceramic coating), and thicker tubing walls add to it.

If you can find one that meets all four requirements, or at least the first three & at least uses 16-gauge tubing, go for it! Otherwise, keep searching... That's what I'd do.


Go beyond the "bolt-on".