Ram Y pipe..shop says bad idea

So I took my truck up to a local muffler shop to put the magnaflow y on and a magnaflow muffler..they put the muffler on but said they highly recommended not useing the y..

I can't remember exactly what they said...something about it getting real hot and the pipe they would use would only last a couple years...also they mentioned possibly burning a valve...they did agree that the stock was restricted. ..but said this would almost be to much air flow...he recommended getting a tuner before I did it so I could get more gas with the added air?...

Again I don't know...it was getting late in the day..maybe he just didn't want to do it

Has anyone heard of these problems ? Is there anyone around that has had this mod for an extended amout of time or miles? .

I definitely want to do it if it's helpful as I have read all over....but definitely don't wanna screw something up...I don't race..but I do haul a trailer very often and just wanna get as much as I can out of the 5.7

You just wanted to replace the y at the end? Cats staying n place? As long as you have cats you have more than enough back pressure.

MANual_puller said:

You just wanted to replace the y at the end? Cats staying n place? As long as you have cats you have more than enough back pressure.

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Not only that but, those cats get a lot hotter than the Y pipe ever will.

I never heard anything about heat being an issue but I had multiple shops in my area as well as have heard multiple members on here say they were told the same thing, that replacing the Y pipe really isn't worth it as you won't really notice much difference.

Replacing the Y won't show any appreciable difference by itself. It's best to just save for headers and an aftermarket y-pipe.

Kotta390 said:

Replacing the Y won't show any appreciable difference by itself. It's best to just save for headers and an aftermarket y-pipe.

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I disagree. Maybe not if only the Y pipe is replaced. That by itself , as you stated wouldn't improve much.
burning a valve...really? as stated the Cats provided plenty of back pressure, and the front 02s keep the mix in check.

On my 2014, the stock Y pipe had a lot of bends and at the same place where they twist and come together the overall diameter is reduced 30%. That restriction and its turbulent flow had to go.

Heat? If the factory was worried about heat they wouldn't have routed the P/S so dam close to the trans pan.

I had my local shop cut the Y pipe out and fabricate two 3" pipes back to a an accelerator ( magnaflow knockoff) muffler , I kept the resos and factory tips. The result is a slightly louder, deeper tone at start up and idle , a roar at WOT , but nice and mellow while cruising.

SO just Y pipe, NO , but as part of a exhaust upgrade or cat back, I think its a must.

Needing backpressure is a common misconception. There are no benefits to backpressure. It is merely a measure of flow restriction, and there are no advantages from restricting flow, with all other things being equal.

That said, open headers usually make less power than a system that has more backpressure, but not because of the backpressure. It makes more power because it has proper scavenging. Scavenging is where the exhaust is pulled out by the vacuum created by the last exhaust pulse. It works best when you have even exhaust pulses, which crossplane V8s do not on each bank. Therefore, overall exhaust flow is increased when the banks are somehow tied together, like with a H, X, or Y pipe. This is why the Y pipe makes more power than open headers.

There will be more wear and tear on the system if you do not have the banks tied together in the exhaust. You will also make less power.

Rupert said:

I disagree.

SO just Y pipe, NO , but as part of a exhaust upgrade or cat back, I think its a must.

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Ok, any dyno results or track times to back your claim? Been around the block with a friend that has a '15 Ram 8spd 3.92 CC truck that did a mufflex 14" I think and then later put a magnaflow Y on it and never saw a gain in fuel mileage and zero difference in butt dyno. Sorry I will just agree to disagree with you.

Muffler guys are generally not mechanics, and certainly not mechanical engineers.
Sometimes they're just opinionated welders and other times they're crooked and stupid...

***no offense intended to real and skilled welders/boiler makers/pipe fitters etc.***

Hell, the Magnaflow recommended vendor in my area quoted me $1200 to replace the OEM with a 22'' managflow. He quoted over six feet of new stainless pipe.
Now, this was not a Cat-back, or a resonator delete; just a muffler swap using stainless spool pieces to make up the difference in size between the OEM and new.
When I called him on it, the Dumb@$$ tried to give me gobble-d-**** (the way the Neanderthals usually do to women--which I ain't--and it really ****** me off when they do it) about needing that much pipe to avoid crimping it around the axle and getting everything to line up.
My reply? "Ever heard of a mandrel you %#@*&!!!? How about Mufflex?--your fired!

So as to your Y-pipe: Physics rule, MIG/TIG knuckleheads drool.


A better flowing Y-pipe can't physically make that area of the exhaust hotter than the constricted factory Y pipe. You are not going to pump that much more exhaust through, and removing the constriction will actually cause less opportunity for the exhaust to impart heat. Dual systems always work best as stated above when cross connected to equalize pressures. So, Y-pipe good, to some extent; aftermarket Y-pipe better than OEM.

Drooling exhaust monkeys? Not so hot.

They said couple things right. 1 tuner would gain you a lot more, 2 the pipe they would use would only last few years as the normal "exhaust" shop would only use aluminized pipe witch is just plain mild steel coated. Our factory systems are stainless a very low grade stainless but stainless non the less. Every thing else he has no idea what he's talking about. You won't hurt the valves the way you hurt valves is cold air getting sucked into a hot chamber and your exhaust manifold is long enough to run it open and not worry let alone exhaust that run down and under the trans. The "to much flow* is also wrong in this particular case (it's possible to have to much flow but it wouldn't be in this case) I have put the magnaflow y pipe on a buddy's truck and he gained some throttle response nothing really in performance and it's been on there for over year now with no ill effects. Also I have to weigh in on the common misconception of back pressure dub shep was really close and got most right but you want zero back pressure. Back pressure would be air flow going backwards into your engine and that would mess a lot of things up. What he got right was scavegeing. Scavegeing is what creates power. As you resrict flow it can actually cause the gas to speed up because your forcing more air through a smaller space. As that gas speeds up it actually draws a vacume and pulls the next pulse out of the cylinder so on and so forth witch is scaveging. If you can get more air out you can put more air in, a Engine is just a big air pump. More air equals more power.

14hemiexpress said:

Also I have to weigh in on the common misconception of back pressure dub shep was really close and got most right but you want zero back pressure. Back pressure would be air flow going backwards into your engine and that would mess a lot of things up. What he got right was scavegeing. Scavegeing is what creates power. As you resrict flow it can actually cause the gas to speed up because your forcing more air through a smaller space. As that gas speeds up it actually draws a vacume and pulls the next pulse out of the cylinder so on and so forth witch is scaveging. If you can get more air out you can put more air in, a Engine is just a big air pump. More air equals more power.

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I think you're confusing back pressure with backflow. Back pressure is a pressure generated as a resistance to flow. Backflow is when the fluid actually flows backward, like in a two stroke exhaust system.

As you said, you can increase scavenging by increasing backpressure, or the flow restriction, yes. It's possible to have a pipe that is so big that scavenging doesn't work like it should. BUT that's far different than creating bends or kinks in the flow that create back
pressure.

My Installer has been Exhaust for decades. Outrageously expensive Exotics/Performance cars to whatever junker comes in the door.

He told me that the Magnaflow 12388 would add a few extra horsepower, the Magnaflow Y-pipe was a complete waste of time. Back pressure would be affected, period. I might notice it, I might not, but low end torgue (may have been low speed torque) would be affected, to some degree.

Now, if I was also doing a Tuner, Long Tube Headers or some other Mod, that Y-pipe upgrade might be worth something. He never said, since I was not doing those things.

I do know that he did say , for the dollar, the biggest improvement I would see was simply the Mufffler upgrade. All that other stuff would yield improvements but no where near the improvement I would gain, from just cost of the muffler upgrade.

Basically, spend that money elsewhere, where the horsepower increase would be greater, for the amount spent.


If this guy had said drop $2K on exhaust, I would have done so. He knows this too.
He knows my needs , style and desires and told me his best opinion on how I should proceed and the Y-pipe was a waste.

Was really an easy conversation.

Installer -- I think .....
Me -- Okay. Do it. I'm gong to go buy some Girl Scout Cookies from your Wife & Kid. Got any milk around here?

I thought somebody had a dyno showing a few HP gains from the magnaflow Y?

By looking at the stock Y, I can see where you would gain some. It would definitely free up the exhaust some but not enough if it cost alot for the install.

I have one and was going to get it installed when I got my 5" tips installed, but my exhaust guy said it's going to be another $100+ to run the pipes away from the tranny pan(like I want) and into the Y. So I'm not going to worry about it.

This is the Y-pipe on mine. It doesn't look all that bad as to restriction, however the crossover part is rather close to the transmission pan. There will be however a lot of air flow to carry heat away.



I ain't never going to change anything here, just interested in the discussion.

you guys might find this interesting, maximum exhaust flow isn't the magic for horsepower and fuel economy, you can throw all that money at your exhaust and you won't see hardly any significant increases if any at all

unless you change the factory manifolds and better flowing cats, anything after the cats is money thrown away

doing a cat back or a muffler will only change the sound of your truck

https://www.youtube.com/watch?v=azPKIjxmmdU

monteholic said:

you guys might find this interesting, maximum exhaust flow isn't the magic for horsepower and fuel economy, you can throw all that money at your exhaust and you won't see hardly any significant increases if any at all

unless you change the factory manifolds and better flowing cats, anything after the cats is money thrown away

doing a cat back or a muffler will only change the sound of your truck

https://www.youtube.com/watch?v=azPKIjxmmdU

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SPOILSPORT!!

I bet you're the kind of guy who blows out a child's birthday cake candles and act like you sneezed too.

Recon12 said:

This is the Y-pipe on mine. It doesn't look all that bad as to restriction, however the crossover part is rather close to the transmission pan. There will be however a lot of air flow to carry heat away.



I ain't never going to change anything here, just interested in the discussion.

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At first I was like you have a plastic tranny pan.??

Never seen the underside of a 8 speed.

Ok just so everyone knows I owned and operated an exhaust shop for years and built thousands of systems nothing will happen to any part of your engine from modifying your exhaust to flow better No sucked valves, burnt valves or heat buildup if flow is improved. Material they said wouldn't last long aluminized steel vs. stainless steel lasting a lot longer no back pressure will hurt the HP department but not the motor less is better but only to a point that's when it hurts your hp. People talk about burnt or sucked valves don't have a clue take dragsters or even a compact car a tractor even a rice burner I've ran hundreds of motors with no exhaust with no problem I even built a 12000+ rpm 1.6L Toyota motor that ran with only 6 inches of pipe for each cylinder never had a valve problem once. So the shop that you went to they were trying to help you make a decision on what you would be ok with, they just may not have had enough knowledge to build something that you would be impressed/pleased with. Or they may just didn't feel like working that day.


05 2500 4dr shortbed 4" lift on 35's, 4" straight pipe, Afe intake

Recon12 said:

This is the Y-pipe on mine. It doesn't look all that bad as to restriction, however the crossover part is rather close to the transmission pan. There will be however a lot of air flow to carry heat away.



I ain't never going to change anything here, just interested in the discussion.

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Doesn't "look like"???

Cut it open and you might change your mind, there is a lot of laminar flow present/ let alone the reducing in cross section: that's what happens when you cram two three inch pipes into one 4 " that's a big reduction.

Pipe Diameter

Rupert said:

Doesn't "look like"???

Cut it open and you might change your mind, there is a lot of laminar flow present/ let alone the reducing in cross section: that's what happens when you cram two three inch pipes into one 4 " that's a big reduction.

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I just had mine done and the pipes coming from the motor are 2.25'' and the single pipe to the muffler is a 3''.... Just what he said above.... Very restrictive at the y-pipe.... They basically mash the 2.25 into a half moon to shove it into the 3'' with the other 2.25.... I can't say that it made any difference but it certainly can't hurt.....