Let The DIY Turbo Manifolds Begin

[cragg56]

I know there are mixed feelings about things from China, but CXRacing seems to be making things simple for those low budget DIY guys to make their own manifolds. I am even debating giving it a shot.

Can we keep this thread constructive PLEASE



or






http://www.ebay.com/itm/6-1-header-m...ht_7105wt_1113
http://www.ebay.com/itm/11-Gauge-6-1...ht_7105wt_1113
http://www.stainlessheaders.com/engineheaderflanges
http://www.acestainless.com/pipe/schedule-10/pg-010wn
http://www.acestainless.com/butt-wel...d-els/s90-g1wn

[sk8rpirate]

this seems pretty cool, would you be going for bottom or top mount

[Bimmerbear]

Not a fan of the wastegate port, but most people probably won't care.

[someguy2800]

go for it but I wouldn't touch either of these collectors. I like my wastegates to function. Building a collector is the easiest part of the whole operation.

[gstuning]

You could always make a twin scroll manifold like so




Now this manifold is twin scroll for a T4 flange, the turbo is a Borg Warner S256, I´m getting 0.6bar@3000rpm on a M50B25 with dual intake cams in third gear, its maintaining VE all the way to 7k. The 3-1 keeps the banks 100% isolated and thus allows for much shorter primarys.

Here below is an even simpler one for a top mount M50 E30 and a twin scroll borg.

The above design is equal length as it matters to the exhaust ports.

Why people always make a 6-1 manifold is beyond me.

[1SLWM3]

^ nice!

[someguy2800]

Why people always make a 6-1 manifold is beyond me.

Yep. Way less efficient and makes a proper wastegate dump impossible

[Captain Bondo]

go for it but I wouldn't touch either of these collectors. I like my wastegates to function. Building a collector is the easiest part of the whole operation.

While I would agree that twin scroll and two x "3 cylinder" collectors generally makes more sense if starting from scratch on a 6 cylinder manifold, the wastegate placement shown in the OP will work fine for 99% of people. That's pretty much standard. I've build at least a dozen header with similar placement and no issues.

[bawareca]

While I would agree that twin scroll and two x "3 cylinder" collectors generally makes more sense if starting from scratch on a 6 cylinder manifold, the wastegate placement shown in the OP will work fine for 99% of people. That's pretty much standard. I've build at least a dozen header with similar placement and no issues.

It is not going to work on a properly designed high efficient system with low backpressure,but what do i know.

[M3equalslife]

Wow pretty impressive!

You could always make a twin scroll manifold like so




Now this manifold is twin scroll for a T4 flange, the turbo is a Borg Warner S256, I´m getting 0.6bar@3000rpm on a M50B25 with dual intake cams in third gear, its maintaining VE all the way to 7k. The 3-1 keeps the banks 100% isolated and thus allows for much shorter primarys.

Here below is an even simpler one for a top mount M50 E30 and a twin scroll borg.

The above design is equal length as it matters to the exhaust ports.

Why people always make a 6-1 manifold is beyond me.

[wazzu70]

Im surprised there arent more people using the Borg Warner units. Very efficient, very cost effective.

Regarding manifolds, the trick around here is to make it shiny. If its shiny, it must flow better!

[Captain Bondo]

It is not going to work on a properly designed high efficient system with low backpressure,but what do i know.

Yes it will. Here's the wastegate exit on my 600hp volvo motor. That had a 1.00 A/R T4 turbine housing and a P trim turbine wheel. Very low backpressure, more hotside than most people here are running. I could run 4psi without creep. But what do I know? I built turbo systems almost full time for several years.





I know internet wisdom trumps real-world built and tested setups, however. So fair enough. Anyone can do whatever they want.

[MTrace]

They also sell them without the port.

http://www.ebay.com/itm/CXRacing-6-1...4d9e16&vxp=mtr

[gstuning]

Yes it will. Here's the wastegate exit on my 600hp volvo motor. That had a 1.00 A/R T4 turbine housing and a P trim turbine wheel. Very low backpressure, more hotside than most people here are running. I could run 4psi without creep. But what do I know? I built turbo systems almost full time for several years.





I know internet wisdom trumps real-world built and tested setups, however. So fair enough. Anyone can do whatever they want.

It will. But what you must then take into an account is how larger is the wastegate outlet and it´s angle in comparison to the turbine inlet flow as well as the distance from the turbine flange(turbine wheel really).

The more backed up the system the less speed at the wastegate port the easier a 90° bend can be used, in the same sense a single 38ID pipe at a steep angle will also work.

[bubela]

subscribed, to try and learn something. Show me the facts, guys!

[gstuning]

Here is one of the analogies I use when explaining air in pipes to regular people.

Imagine yourself walking down a hall way that is exactly as wide as you with your hands out to the sides , i.e. your hands are thouching the walls. Now the hall way never changes diameter in this example. Imaging coming up to a easy bend, no problem you remain in the center. And then imagine the same at your highest running speed, still no problem the bend is so wide.

Now imagine you are further down the hall way in a straight section running as fast as possible with your arms out. Now there are two doors ahead, one is straight on and the other is to the left. Now while running as fast as possible you don´t know which door to pick, try and imagine picking the door on the left while you are running as fast as possible and only 2ft before the door is on your left. How likely are you to make it into the door? How easy would it have been if the doors where adjacent in a 45° Y split formation over the 90° bend? What if the door had been twice as wide???
LOW BACKPRESSURE SCENARIO



Now imagine that this hall way is full of people, at the beginning of the hall way there is a massive rush of people getting into the hall way as it was literally empty when the door opened to it, after a while everybody has spread out nicely but as you get further down the hall way there seems to be slowing down in front of you, now imagine you are coming to the two doors where one is straight ahead and the other to the left, now you have slowed down ALOT so while walking how hard will it be to make it into the left door even if you choose to pick it 2ft away from it? How crazy easy would it be if it was twice as wide?
HIGH BACKPRESSURE SCENARIO

Now imagine that your entering a hall way through a door, right after the door everything is dead slow and your hardly moving. Its really crowded, now behind you people are going back into the door as its less crowded and basically nowhere else to go. Now you are in the room and it´s nice and spaceious. However the room is getting smaller constantly and now its getting crowded again and there is NO where else to go but through the door again and into the hallway, but thanks to the non stopping room getting smaller the push from you overcomes the people in the hallway and they all get shooved onwards. However some people got left behind in the super small room.
#1 CYL runner is so short its opening right into the turbo collector

Now imagine that your leaving the room FIRST. Right up front. Now it´s simply crazy crowded in there, and as you get out into the very spacious hallway you seem to hit alot more people, you bump into them a bit but things don´t seem to move much thanks you hitting them, thanks to the people behind you pushing while you move up the hallway you do move along, as you move up the hallway you notice that alot of people are getting pushed out of one of the rooms, as they all clear out they block your path, you figure I´ll just take their place and get into the room instead at least your not just sitting there doing nothing.
You where stuck in a log manifold at high backpressure or a low volume single scroll manifold

You can also replace the hallway with a highway.
I can´t dump it down any more then this

[Captain Bondo]

No offense Gunni you are a good dude and a fellow VEMS guy, and you write lots of great posts, but in this case - you can write as many novels as you want. I will take real world building and testing. In this case the requirements and solutions are simple.


Here's what I know:
I know for a fact that the following parameters work, for 2.3-3.0L engines:

1) 1.5" schedule 10 wastegate port (Also, for reference, 1.5" Sched 10 is ~44mm ID, not the 38mm you mentioned. Hopefully it goes without saying that you don't use a 38mm wastegate on a 44mm wastegate port. That would be mistake #1)

2) Placed at something close to a 90 degree angle from the merge collector

3) reasonably close to the turbine flange

4) with a 44mm wastegate

5) recirculated into a free flowing exhaust

That config will regulate boost just fine for 99% of applications. On a really aggressive 6 cylinder, 2.8L+ build, I would use a 2" Schedule 10 port and a 60mm wastegate (like in the previously shown pics - that was a T67, so really that setup was built to support 700whp+) or twin scroll with twin 38's or 44's. We're talking 700whp+ though with a large T4 turbine housing and 65mm+ turbine wheel.

I've also done twin scroll this way- this is a single 44mm wastegate, twin ports at 90 degrees from the collector, 500whp 2.3L engine on an HX40 Super 14cm.





This manifold is for a 2.5L 600whp drag motor with a twin scroll HX52 on it. Has a similar port on the back. Twin Tial 38mm MVS. Granted it only runs race fuel and never needs to run low boost, but boost control is fine. It's a proven approach.



There's no reason the wastegate ports on those collectors won't work with a 44mm wastegate provided someone is not trying to run very low boost on a huge, very low restriction turbo (not a common scenario). For the vast majority of folks here running 60-62mm turbos with medium to large A/R T3 housings or smallish T4 housings, it'll be fine. Seriously.

[gstuning]

I was just trying to explain what happens in the simplest terms in some scenarios. If something you build works it will be because it follows the laws of fluid mechanics.

I never said that 90° wouldn´t work, at some gas velocity for a given port size it will not work. At either lower velocity or larger port size it will. No doubt about it.

[bawareca]

...............

Everything you posted is fine,and I am sure it is doing it's job.It is the THING on the picture on the first post that is not going to work properly on the 99% of the installs.No freakin wayyy.



Arguing for the sake of the argument makes us all internets heroes

[someguy2800]

[Captain Bondo]

Actually, those runners you drew the arrow on are aimed at the wastegate port the most. It would be the front ones that would have the worst flow path (gas has to make a 90 degree or sharper turn). At any rate you're all making a bigger deal out of it than it really is. There's a pressure drop across the turbine wheel. It is much higher than the pressure drop across the open wastegate valve.

A 1.5:1 exhaust back pressure to boost pressure ratio is pretty normal on a street car. That means that at 15psi of boost, there is 22.5psi of exhaust pressure inside that collector. When you open the wastegate, those exhaust gases want out. At that point in the manifold the gas speed has slowed significantly because the exhaust comes in pulses and the cross section increases drastically at the collector.

Yes you see people with wastegate ports far away from the turbine flange where velocity is still high, aimed away from the flow, etc, and small wastegates that usually re-enter the (often restrictive) exhaust quite poorly, with all kinds of crazy creep problems, but I have seen far worse than what is pictured work fine with a 44mm gate.

It's just painfully obvious that most of the opinion in this thread is that based on internet mob mentality and not rel experience. Could you do a terrible job of using the pictured wastegate port? Sure. Could you stick a 44m wastegate on it with reasonably well thioought out plumbing and do just fine? My opinion is yes you could.

[someguy2800]

Your right in the same sense that using and air mattress as a boat works just fine. All we are getting at is why do it wrong when its so easy to do it right? boost control is not the only objective, reducing turbulence in the exhaust manifold makes more power, reduces manifold pressure, and maintains velocity to the turbine wheel. Turbos aren't just spun by pressure differential, inertia is a big player too. Each to his own.

[Captain Bondo]

Meh. Every wastegate arrangement will be based on several design tradeoffs. They're a necessary evil. I don't think it's valid to start pointing at such nebulous effect like "oh it will introduce turbulence in the collector." Well duh of course it will.

As an aside- inertia is a weird term for what you're trying to describe. It is pulse energy. It's not the inertia, as that implies mass. It's an energy wave. Cylinder blowdown, more specifically. Pulse energy definitely helps spool turbos but the spool up process is transient. Wastegate function occurs for the most part after the system reaches steady state.

How do you build manifolds btw? Any pics?

IMO all you can do is keep collector volume low (keep the actual wastegate port short), try to aim the wastegate port so natural exhaust flow can get to it (90 degrees or less to the collector center axis), and mount it close to the turbine flange.

How well those things can be done are mainly determined by how much physical space you have. The chinbay collectors more-or-less do those things. Maybe marginally, but if you're building an uber ballstothewall million hp superturbomaster setup then build the damn collector yourself. But for most of the guys who just wanna stick a 35R on their car and have some fun, it'll get the job done and within that context, any issues with that placement are purely academic. IMO.

[someguy2800]

all made with long radius 16ga mandrel bends. Wastegate dumps are tangent to the flow path and downstream of the collector. The only thing I'm not happy about is the difference in length. I will rectify this if I ever build another but I was out of tubing.

Inertia is a weird term for what you're trying to describe.

no actually thats exactly the term I wanted

But for most of the guys who just wanna stick a 35R on their car and have some fun, it'll get the job done and within that context

good enough for me. this is the point where in person I would buy you a beer and talk about something else. How are the twins coming along?

[gstuning]

As an aside- inertia is a weird term for what you're trying to describe. It is pulse energy. It's not the inertia, as that implies mass. It's an energy wave. Cylinder blowdown, more specifically. Pulse energy definitely helps spool turbos but the spool up process is transient. Wastegate function occurs for the most part after the system reaches steady state.

Cylinder blow down is the process of evacuating AIR out of the cylinder. The sonic pressure wave is so miniscule as a pulse on to the turbine wheel it has little effect compared to the impact by a pulse of air mass. The sonic pressure wave can help at the exhaust port as it´s only affecting air.