Y pipe vs dual inlet muffler?

Looking at exhaust options.. I read a lot about x pipe vs h pipe, but I might forego both of them and opt for a y collector instead. Basically, stock pipes all the way back into a Y collector where they would go through the stock muffler, into a single 3" In/Out muffler, out the stock tailpipe.

I'm really wondering if there is a difference between a y pipe into a single in/out and the stock dual inlet single outlet? My brain wants to say that the y collector should have better scavenging than dual inlet muffler with the more even sound/pulse advantage of a y pipe. I would think that it should also help keep exhaust velocity up, especially if I used a straight through type muffler.

Anybody done this? Any ideas? I will probably bring some parts to my local exhaust shop and ask them to stitch them in for a road test before burning it all in.

Here is my "inspiration photo/video" (those of you who deal with designers understands what I'm talking about). He also has an X pipe, which I'm not opposed to, but for simplicity sake, a y pipe would be simpler.

 

I found that content creator when looking at information on Helmholtz resonators. In another video he redesigns the system (mainly for sound management) he showcases in the video you linked.

 

I've seen the same video about Helmholtz resonators. I studied the principle in college back when but it was nice to see it put in to practice.

 

Reposting your posted video from the S/C thread @Saltyhero13

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This was the one video contradicting X and H pipe. He does show dynos form Engine Masters:

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He brings up a couple of good topics such as laminar vs turbulent flow (he doesn't call them out by name, but those are the principles he's describing) and scavenging. What he's saying about X pipes seems logical; as the exhaust gasses merge at the x pipe, the benefit from scavenging, but then as they exit the x pipe, there are a couple different things that could be going one. I've seen a few different designs for X pipes and I suppose some may affect flow and velocity different than others. But that doesn't necessarily mean it is practically correct (not debating that it is or isn't, just saying that theory and practice are sometimes different).

 

You’re right about a y pipe being better than a 2in 1 put muffler. You’re also right about using stock tubing everywhere except the muffler.

there’s ways to further dial on the sound that you’re looking for. Like using a muffler in each bank before the y pipe instead of one single muffler after.

There’s also issues you will run into when making your own Helmholtz resonator. We have that completely resolved tho with a bolt on solution.

Rather than guess and hope a muffler shop creates whatcha want, my job is to consult over the phone what you want, then build it and ship it as a direct bolt on. Helmholtz resonator and all. You’re in good hands, I’ve personally prototyped hundreds of exhaust systems on tundras. And built tens of thousands of production systems. More than any other person on earth, and certainly all of the other aftermarket manufacturers put together.

search here and YouTube for BAmufflers 8”. That’s our most popular system. And call to speak directly to the engineer of your next exhaust system.

Keith 760-877-4234

dirtydeedsindustries.com

 

Ordered up a y pipe and a 3" center in to 3" center out muffler today. When they show up, I schedule a time for the muffler shop to stitch them in. I'm curious to see the difference.

 

if the drone is more than you want give a call, we build a bolt on helmholtz resonator to kill it. 760-877-4234. Keith

 

pretty much all the rules are different for a 5.7 using stock manifolds. There's actually way less things that work. What does work:

1. keep as much of the stock as possible
2. You have to exit thru the stock tailpipe
3. use a flow thru muffler and a smooth transition Y pipe
4. use a helmholtz resonator to kill the drone.,

 

Keith, why do you think toyota used the oe muffler as a y and not just a single inlet muffler?

 

Cost savings. Weight savings. Size packaging.

they didn’t care how much power it gained or lost, they hit their target Hp level with that muffler. This is why there’s so much ‘free’ Hp, torque, and most importantly: low end torque locked up in that stock muffler.

 

I believe @blenton is ultimately supercharging his truck also, so i’m sure that changes the rules as well.

 

Correct. But I've got a few months before it shows up and I already got a shipping notification for the muffler, so I'll play around with it until the new set of lungs show up. The Flowmaster I've had on for the last couple of years sounds great an isn't too loud, but I've been wanting to see if there really is a difference between a dual inlet muffler vs a y pipe and single inlet. I also plan to have them flange the back side of the y so that I can easily swap mufflers if I decide I want something different down the road.

My sequoia is stock and I don't have plans for a S/C on that. Yet... So we will see what lessons can be learned. I don't plan on modding the sequoia as it's a great road trip family truckster from the factory. Bilstein 5100's and pulling out the interior to install sound deadening all around is about as wild as it will probably get. Funny thing is, I feel like the sequoia has more off the line up to about 2200 rpm just puttering around, but after that my truck pulls harder. The tundra easily weighs 1000+ lbs more which may explain some of it.

 

@blenton my experiments of oe muffler vs 2 in 1 magnaflow mirror exactly as you describe the comparison. 2k-2200rpm is where the oe muffler loses out big time. Off the line OE is great

 

It does!! Now there’s no reason to run long tubes. Follow the rules for naturally aspirated with stock manifolds. You’ll save $$ and have way better low end torque.

 

Just to confuse things further… Lexus uses what can be called either long X or fat H pipes on their UR series V8 dual systems. LS 460 pictured.

 

Lexus uses cherry bombs...?? Nice!

 

LOL! They even use two different types, F sport is straight through w/ packing, normal is straight through but has resonance chamber.

 

knowing toyota, that's purely for sound. it's odd size and shape isn't a guess with them.

 

Guess I need to make an appointment with the muffler shop…

 

when building performance exhaust you really want the smoothest, most direct path with correctly sized tubing, as possible. Making an unnecessary chamber thingy and a muffler with walls that block the exhaust flow hurt performance.

 

I know y'all are talking 5.7's. but I have a question about my 4.7. I have the JBA LTs on my 03 going into an aftermarket Y pipe and then the TRD cat back. The TRD catback has two in-line resonators, then a single in dual out muffler. My question is if I eliminated the two in-line resonators and welded in a straight pipe in their place, what would that do for my sound and power? I would assume the exhaust would get a little louder and flow a little better. My only issue with the TRD catback is how quiet it is. I like the low bass rumble. I just want it to be a little louder

 

Take out one resonator at a time. They don’t do anything for power. Only sound.

 

“I’ve discovered that when supercharged, no matter what exhaust you have, you make the same power.”

From this thread, post number 6. https://www.tundras.com/threads/supercharger-and-stock-exhaust.62608/#post-1639236

Hmmmm…

 

If you had an exhaust restriction (I doubt you do/will) wouldn't you see it on your boost gauge (that you don't have)?

 

Are you supercharged?

 

There was a guy on tacoma world who dynod his truck with a magnaflow and a flowmaster. Same pipes.

the flowmaster made more power shockingly

 

Follow along now, kids…

 

I would guess one is using reflection vs the other using absorption.
https://youtu.be/RWTARjxiqlo?si=lvCjG6TU2II8LUM1&t=1020

 

Top is a good example of one
Burns Stainless has a good video on merges:
https://youtu.be/Q8Y0dNQIcvw?si=bOj2nNwATimzfOq-

 

Maybe the Land Cruiser muffler will be the hot ticket for supercharged trucks. Same muffler design, but with pop off valves.