Alright, I've read plenty that just deleting the mufflers can cause a loss of torque. Also read that it's not less backpressure that causes the torque loss, but the loss of velocity because of the bigger pipes.

So here's the idea: What if you delete the mufflers for sound, then replace them with a smaller pipe, like 2" or 1.75" or something smaller than you'd usually expect? The goal is to reduce backpressure but maintain velocity.

What size are the mufflers' internal pipes? It may make sense to bolt on a straight pipe of the same size.

 

The mufflers' internal pipe sizes look around 1.75" to 2.00"

People believe back pressure is a myth, because they only view it as "full restriction" with a value of 0, so the term is not favored. Although, if you consider back-pressure can have various levels, than it actually makes sense that it can be synonymous with velocity.

I've been through many different exhaust setups, about 6, with and with out headers, with and without resonators, mufflers, third cat, with and without Y pipe, and various aftermarket mufflers including chambered, stock, and glass packs.

If everything else is stock on the exhaust - two cats, third cat, and two resonators - deleting the two back mufflers really do not effect the low end. 2.25" is fine which matches the pipes before it. Drone is not too bad, but because there is no weight on the back of the exhaust pipes anymore, and sound is amplified/reflected more, they are still subject to drone.

If you are going to straight pipe everything, this effect the low end more, but still not that much - the velocity from the Y pipe keeps this in check, but honestly, this will drone very badly.

Changing to an X-pipe or no-cross-over will effect the low end, but it is slight. For me, my goals were a good sound, low-end and high end response, but a balance between that and drone. I think an x-pipe, or divorced pipe with straight pipes, or a full 2.5" system will hurt torque the most, and I wouldn't recommend this.

My current set up: Headers>Reformed 2.25" secondaries with no X or cross over pipe>No resonators>Stock rear mufflers
No drone, good low end response, but this is mainly due to the headers and tune. This exhaust set-up was helped designed by a gentleman at Aston Martin, after telling him my love for how the V8 Vantage motors sound. This is all stainless steel, and is almost identical to the Vantage. It's a very unique sound.

Basically, the 1UZ and 3UZ have a lot more low-end torque than people would think. Other than a full 2.5" exhaust, or complete straight piped system, which I would not recommend, a lot can be done with our exhausts. The 3.0L motor will be a lot more sensitive to low-end torque with exhaust changes.

 

Some excellent info here. Thanks.

 

GS400V8, lemme see some pics of your exhaust system.

 

Well now I wish I took some when I was up on the lift. I have some pictures, but they look odd from the ground.
Instead I have drawn a diagram of mine and the stock system.
The second picture is the custom muffler delete setup I just took off, it was too much drone with my mods.
Also, my 2.5" system comment doesn't apply to supercharged 1UZs unless it is fully straight piped

 

Dont wanna thread jack, PM'ed you bro.

 

I demand to hear your exhaust. please and thank you. and some pics too.

 

Okay here is a video and some pictures. You can tell there is no joiner pipe between the banks in between the banks, but there is a reinforcement bar like the factory had.

When you have an X-pipe, it can help with scavenging. But with well designed headers like the PPE, or the ones on the Astons (my goal for sound), an X-pipe or H-pipe isn't always needed. Some Vantage guys saw gains with an X-pipe, but Aston doesn't put them there for a reason. When you cascade the sound and pressure waves from each bank into eachother via a joiner pipe, it can cancel out frequencies. Some pulses may be louder, but with no joiner pipe you are letting each bank only cancel out any sound waves it might have on one bank, which is much less likely than shoving the banks into each other.

Some hear an X-pipe as exotic, which they can be, but listen to any Aston Martin Vantage V8 or V12. They are both odd-firing engines, with 90 degree cranks, and no X or H pipes stock. Tell me those don't sound exotic! They have higher revs than us, but the UZ motors have a very distinct sound that share 4 cams and 4 valves per cylinder like the Aston, so thats what my exhaust was designed for.

Video-
Pics-

 

sounds pretty good. question is, did you lose low end torque? and how does it feel when your doing 70 and punch it. something ive realized about exhaust is that if you looking to get rid of the raspy sound, than you need to
have a large body muffler. like really big like a factory one. not a magnaflow that measures 5x8. some of the best sounding cars ive ever heard had huge mufflers on the back with no resonators. and yes, the material the exhaust is
made out of has alot to do with it.

 

Thank you! It's still not as cool as supercharged UZ though, that's for sure! I still wish it was louder like my previous set-up was, but I couldn't tolerate the drone after 3 months.

I don't feel any low end torque loss, even with no joiner pipe. This could be do to the headers, although, the rear mufflers are not the most free flowing. When I'm going 70 and punch it, it feels very tight in the low end and really pulls hard in the midrange to redline.

I agree, that's why after going through many mufflers, I'm back with the factory, but I still wish it was louder sometimes. Most brands including Maserati, Aston and even in the ISF have one section of the exhaust muffler that opens up when you go above 4kRPM. It is essentially straight piped, but the weight of the muffler (heavy steel) keeps it from droning too much. In the future, I've thought about cutting open the factory muffler, and placing my previous glass pack in the case to get the sound but no drone.

 

GS400V8, I like the sound. Is it possible to get the same characteristics but quieter? I want just enough aftermarket touch to make somebody look twice but not so loud that it draws attention.

Maybe Tanabe Medallion mufflers? Would that do anything if I left the rest of the system alone?

 

It's actually not very loud at all. When accelerating full throttle away from someone, like a drive-by, you really can't hear much. Which is why I miss my previous pictures setup with only glasspacks. It sounded mean.

if you have a stock system running into Tanabe mufflers, it definitely won't be loud either. The turbo mufflers used in those have a lot of absorption material, as do the long torpedo style stock resonators (glasspacks) and the third cat.

If you removed resonators and third cat into Tanabes, it will sound about level with my set-up, maybe a half decible louder.

In fact, listen to this clip. He has headers, a cold air intake, and the Tanabe. Definitely not loud:

 

THAT is excellent. I'd dig that. So is the Tanabe setup typically just mufflers or is a full catback system?

 

Sometimes they are sold seperately, but it should be a kit with a Y pipe. Keep in mind there is the more quiet touring, and the hyper.

The problem with kits is sometimes they dont always line up perfectly and danthedj, a member on here, found this to be true with the Tanabe. Here were some more thoughts
I had:


Quote:
Originally Posted by GS400V8
The Tanabe is definitely one of the better systems out there.
The good: it's stainless, and deletes the resonators, not too over the top, mild drone.
The bad: the mufflers and tip are not at an angle like the factory mufflers, the mufflers will hang lower and be more visible which looks a tad ricey to me, even worse for us lowered guys. Also, with kits it is sometimes hard to line up the exhaust tips with the bumper cut-outs, vertically and horizontally. Meaning, one could be perfect, the other could be touching the bumper cut-out, or anything between. This is because all cars are different when it comes down to the inch or half-inch. Also a little expensive.

My preference: I personally would get a custom exhaust made, something stainless steel, delete the Y-pipe and get an x-pipe (I actually did no joiner pipe, so no x or h or y pipe) and that will run you about $300-600 depending on what you want done. It will also fit perfectly

 

As a DIYer wanting to be able to do everything myself: Can I get away with just the Tanabe mufflers and still make it sound cool, or does the Y pipe and resonator delete have to happen too?