CoedNaked

I got a buddy who's truck is completely bone stock - it's a 2003 Tacoma TRD 4x4 TRD Offroad package with the 3.4 liter obviously.

Please confirm - the 3.4 liter stock exhaust pipes are 2 1/4", is that correct?

Also, the stock exhaust in those trucks, is that made of 409 stainless steel?

What I want to know, is if you have just replaced the muffler on your truck and kept the stock pipe and what did you notice as far as performance goes? What brand of muffler? Considering the mufflers would be different lengthes than the stock length of muffler, I'm assuming you might have had to add a piece of pipe in there? Did you use clamps or have it welded, etc. ?

William439

You gain performance by reducing the restriction in the muffler and also with the larger diameter pipes. My borla exhaust uses a 2 1/2 inch pipes from the cat back and a free flowing muffler. You can weld the pipes but the borla kit uses clamps which is what I used since I don't have a welder. Your going to want to use a larger pipe if you are trying to gain performance, but if you can find a free flowing muffler that uses a 2 1/4 pipe I guess you can weld it on the stock exhaust. But why do that when you can replace the whole thing with much less effort and gain more power.

CoedNaked

Yeah my only issue here is cost. For instance you can get a Borla Turbo Muffler for about $171 CDN in 2 1/4" size or you get a Borla catback for $500+ US. The Borla catback is probably 2 1/2", so yeah it'd give more performance, but I'm talking more performance on a budget IE just replacing the muffler and how much of a difference it actually made. Even getting a local shop to mandrel bend it is fairly expensive, although still cheaper than buying a catback system.

William439

Well unless you have a welder or someone who is willing to cut the old muffler off and weld the new borla on, then you have a problem. The stock exhaust is welded fully from the cat back. If you can find someone who will weld the borla on then you will gain some horse power since the muffler is less restrictive, but it won't be as much as the full system (which isn't that much performance gain to begin with). It will sound alot better and if you get a stainless tip from the local auto parts store then it will look and sound like an exhaust, but it won't get you as much performance.

CoedNaked

Well what would you figure an entire system nets you performance wise? AS opposed to say what you suspect a higher performance muffler might gain you?

Jason B

2.25 inches stock, and stock tubing is not stainless it's aluminized steel.

hupptoy

I just added a 2.5" x 18" Magnaflow (4" x 9" 18" Body 2-1/2" C/O 11256) on my stock pipes on my 3.4 4Runner. My OE muffler was splitting down the seam and was starting to rattle at idle. Sounds MUCH better.

My pipes measured 2 3/8 OD and fit nicely inside the 2.5" muffler. Local muffler shop welded on the muffler, a short piece of tube and hanger for $40 (I had already removed the stock muffler with a sawsall).

The OE exhaust tubing is NOT alumized steel. It is a low grade stainless steel (ie. not 409). This has to do with the 80K emissions warranty. Almost all new cars have SS exhausts for this same reason.

I doubt there is enough difference between a cat back system vs. just replacing the muffler to justify all the extra cost.

hupptoy

CoedNaked

Hupptoy, Thanks for the response.

My understanding is 409 grade of S/S IS low grade stainless steel and what is now an OEM requirement for stock exhaust systems. 304 S/S is the cats ass of S/S for exhaust system. Again my understanding.

So you just kept the stock 2 1/4" pipes and welded in a 2 1/2" muffler and a section eh? Interesting I guess.

I would imagine if it was 2 3/8" OD it is probably 2 1/4." I believe it is all based on "nominal" diameters i.e. not neccessarily exactly the measurement.

hupptoy

You are correct on the SS grades, I had them backwards. 409=low grade, 304=good stuff. 304 is overkill for exhaust unless you need to polish for a show truck...

But, just to clarify, the OE exhaust is not aluminized steel on trucks with the 3.4. Probably was aluminzed on our 93's though.

And my exhaust routing is only temporary (OE muffler was shot...) until my wife finds her a new car. Then I can do a few more mods like lift, replace running boards (she is only 5' 3" and needs the running boards...) with sliders and more aggressive tires along with changing the exhaust routing. I bought the 2.5" muffler now so I would be ready for future plans.

hupptoy

CoedNaked

Hupp Toy,

Do you think it would be worth it to buy a 2 1/2" borla muffler, and have a reducing flange (to fit the 2 1/4" stock pipes between the cat and muffler on to the muffler) and then get a custom pipe made and run 2 1/2" from the muffler out?

So the exhaust would be 2 1/4" OEM stock pipe from the manifold to the cat, 2 1/4" OEM stock pipe from the cat to the muffler, the reducer (or in this case, "increaser" adapter/flange and then a 2 1/2" borla muffler, and 2 1/2" from the borla muffler out?

hupptoy

If it were me, I would buy the muffler in a 2.5" and have the 2.5" pipe exit right in front of the tire. Get rid of everything that would have gone over the axle. I may do this once I get rid of my running boards on my 4Runner, but it is easier on a pickup (more room).

I did this on my 93. Had to shorten the pipe in front of the muffler a bunch, then after the muffler, put on a 45 deg bend pipe and then out the side in front of the tire. Couldn't find any pics though.

Just my opinion and what I like for looks on an exhaust. I am in the midwest with lots of domestic trucks with mufflerless duals running out the back (yeah even on 4 cyl. s10's) and wanted my exhaust to be a little different since I am in the severe minority by driving Toyotas (Delphi headquarters and several DaimlerChrysler plants 25 mins away) so obviously different is good...

hupptoy

TheDarkKnight

HuppToy,
I have a couple questions.
I was thinking of the same thing. Having the exhaust come out in front of the rear tire.
1. The Magnaflow, how is it for sound? (I want to keep it as quiet as possible).
2. I think it was on a Ford SVT pick-up, there was a recall due to the exhaust causing the center cap to turn green (not sure if it was due to the heat or the fumes). Did you encounter anything like that on your 93?
3. Exhaust fumes in car. On your 93, did you have any probs with fumes coming up and into the cab?

Hah, I am on the other side of town!
Nissan Tech Center is 10min away, Bosch is 10min away, Toyota Tech Center is 20min away (well, due to M14 construction, its about 35min now...).

tdk

2002 SportEdition

I also had my 2.5x18 magnaflow for TWO (2) WEEKS on my 2002 SE. It is LOUD, people look at you when you pass by. I put back the OE after that and gave the guy who did the re-work the Magnaflow (since he didn't charge me for the rework).

It's loudest at 1800 to 2200 RPM, real nice at idle or above 3000 RPM.

G'Luck

hupptoy

1. I am liking the sound of the 18" Magnaflow so far. I haven't had the same issues as 2002SportEdition with it being too loud, and haven't turned any heads with loud sound (of course the "locals" in the domestics w/out mufflers do...). I do agree that it is loudest about 1800-2100 rpm, but I don't feel it is too loud (even w/rear window down).

2. I am sure that a blown V8 putting out over 350HP has a little hotter exhaust than our little V6's, but I had ZERO issues on my 93.

3. The exhaust was still well behind the cab on my 93, so there was little chance of fumes coming into the cab, no mattter which windows were open.

Looks like some others are saying the 18" body is too loud, but I have not had that experience (yet?). But maybe you're buddy would be better off with the 24" body if he is worried it will be too loud.

hupptoy

TheDarkKnight

Thanks for the info Hupptoy,
I need to get a new muffler soon (the current is starting to fall apart).
Hmmm...
Has anyone put in a 24" Magnaflow?
If I cut install it as far front ward as possible, I wonder if I can still have the exhaust pipes come out in front of the rear tire?... (Heh, too lazy to get down on my back to measure?!)
The rig is going to become my wife's ride later this summer, and she has already informed me that she expects a "quiet" car (sobs!)

tdk