3.3t manifold research

7thSonEngineering

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I purchased a 3.3tt turbo manifold to research the possibility of "Porting" the inside to allow for more flow and less back pressure. My thoughts are that this would benefit oem turbos and Stuffed turbo users.

My initial findings are that the manifold is...

-Cast stainless steel
- Has very thick walls

From my research cast stainless steel is very easy to weld. I of course tried to weld it and I was successful with my first attempt. My next objective is to flow test the oem manifold and then cut it in a strategic spot so that I am able to take a die grinder to it and widen the choke point and entrance to the waste gate area. After this is complete I will weld the manifold back together and flow test it again.

If anyone has a better idea for opening up this manifold please comment.

Attached are photos of the manifold, quick weld and my ideal cut path.
 

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This is a fantastic project. I'm surprised it's thick enough to make porting worthwhile, although TurboKits claims they do it on their TK700 kit (link below).

The two suggestions I have are:

- Consider creating a jig while the manifolds are in one piece. Even if it's quick and crude (a plate bolted to each end, then welded to a simple frame), it'll let you locate everything when you re-weld, and give you the option to make bigger changes. Like...

- Once you cut the narrow point, measure where it starts to neck down in either direction, and see if it's worth cutting out the bottleneck and replacing it with a piece of tube. The above jig will make reassembly much easier.
 
Legend... following with interest.:thumbup:
 
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My next objective is to flow test the oem manifold and then cut it in a strategic spot so that I am able to take a die grinder to it and widen the choke point
Any progress yet?
 
Yes,

1. I devised a way to port the whole manifold without altering the orientation or geometry at all. This is important because everything will bolt back up perfectly after I finish porting the manifold

2. Currently looking for a shop in PA to flow test the manifold I have before I cut into it and port it. I want before and after flow bench data because I may turn it into a service.
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
I devised a way to port the whole manifold without altering the orientation or geometry at all.
Do you mean increasing flow from engine to turbo? Or venting/wastegating the excess flow upstream of the bottleneck? I believe the latter is what John at Torq was talking about doing.
 
Do you mean increasing flow from engine to turbo? Or venting/wastegating the excess flow upstream of the bottleneck? I believe the latter is what John at Torq was talking about doing.
Both will be measured and addressed
 
In the actual car, is there room for a larger pipe? Was wondering if chopping the pipe, putting a flange on the turbo, then fabbing up your own larger diameter pipe is a option
 
In the actual car, is there room for a larger pipe? Was wondering if chopping the pipe, putting a flange on the turbo, then fabbing up your own larger diameter pipe is a option
Anything is possible. Especially since the manifold is easily welded. My thoughts are to keep it simple stupid

I imagine I could cut, port and reweld a manifold in 4-6 hours and ship it back out to a customer
 
Anything is possible. Especially since the manifold is easily welded. My thoughts are to keep it simple stupid

I imagine I could cut, port and reweld a manifold in 4-6 hours and ship it back out to a customer
Have you dynoed your car with the stock manifolds/housings as a baseline? I can't imagine a restriction that tight was done by accident, so I'm sure it plays a role in that 1300 rpm spool, but I'm not sure how much.

I'd happily give up 500 rpm of boost threshold for a bigger top end, so I'm curious to see how a freer flowing manifold would impact spool at the low end, the torque falloff from around 4000-4500, and the power falloff past 5500.

Even just keeping torque flat an extra ~1000 rpm would make the power curve go from flat to increasing toward redline (no more short-shifting).
 
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From interior to exterior to high performance - everything you need for your Stinger awaits you...
Honestly, Id just love to see a bigger manifold then stock. just gaining a full half inch in diameter over stock would be huge

Would make hybrid turbo setups way more viable. Also would be better then having a dump welded on
 
Have you dynoed your car with the stock manifolds/housings as a baseline? I can't imagine a restriction that tight was done by accident, so I'm sure it plays a role in that 1300 rpm spool, but I'm not sure how much.

I'd happily give up 500 rpm of boost threshold for a bigger top end, so I'm curious to see how a freer flowing manifold would impact spool at the low end, the torque falloff from around 4000-4500, and the power falloff past 5500.

Even just keeping torque flat an extra ~1000 rpm would make the power curve go from flat to increasing toward redline (no more short-shifting).
There are plenty of stock dyno whp examples on this forum. I don’t think Kia/Hyundai designed these with the thought of people pushing 500whp in mind. I believe they designed them for fast response and great reliability.

A tight restriction has nothing to do with the turbo spool besides slowing it down. The ar. Controls the turbo spool. So likely after my modifications the turbos will spool better, the engine will pull harder up top and the exhaust will sound better

Time will tell. I reached out to a cylinder head porting company to see if the will flow test the manifold
 

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A tight restriction has nothing to do with the turbo spool besides slowing it down. The ar. Controls the turbo spool
If the restriction gets very tight and then opens back up enough to undo the increase in flow, I'd agree, but if it's just smoothly necking down on the way to the turbo, it should effectively reduce A/R: smaller Area means higher velocity for the same flow, until that flow is so restricted it chokes.

I hope I'm wrong and opening it helps all around, but part of why I asked about a dyno on your specific car is that I don't know how dramatic the change will be on the low end.
 
Great work ... I looked at all avenues of this and gave up...

So many cars running 10's (on the internet with a dragy lol) and even with stock cats *koff*

I know what I have tried and I know how many times I was told flat out "won't work" "don't waste your money" so I have given up...

We have 2 cars down here claiming all sorts of dyno figures but neither has ever been down a drag strip !!

And they have custom steam pipe manifolds and BIGGER turbos but everything is secret phucking squirrel.
I will find the photos and share if you are interested?

If my car doesn't sell next year it will have a 7.3 Godzilla FORD v8 and 10sp auto transplant !

Maybe

Probably

:whistle:
 
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If the restriction gets very tight and then opens back up enough to undo the increase in flow, I'd agree, but if it's just smoothly necking down on the way to the turbo, it should effectively reduce A/R: smaller Area means higher velocity for the same flow, until that flow is so restricted it chokes.

I hope I'm wrong and opening it helps all around, but part of why I asked about a dyno on your specific car is that I don't know how dramatic the change will be on the low end.
Understandable, I think we are only a few days from discovering how much it necks down and how far it stays necked down.

I have a question for you. When a Kia stinger blows a head gasket which head blows first, driver or passenger?
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
Great work ... I looked at all avenues of this and gave up...

So many cars running 10's (on the internet with a dragy lol) and even with stock cats *koff*

I know what I have tried and I know how many times I was told flat out "won't work" "don't waste your money" so I have given up...

We have 2 cars down here claiming all sorts of dyno figures but neither has ever been down a drag strip !!

And they have custom steam pipe manifolds and BIGGER turbos but everything is secret phucking squirrel.
I will find the photos and share if you are interested?

If my car doesn't sell next year it will have a 7.3 Godzilla FORD v8 and 10sp auto transplant !

Maybe

Probably

:whistle:
I have 5 ideas that will take this platform to a new level

1. Ported turbo manifold
2. 1000hp Air to water intercooler
3. easily done transmission upgrade ;)
4. Drive train upgrade ;)
5. Iat sensor relocation kit (my design)

All of these mods iv done on my previous build so I know they work.


I guess I understand people keeping secret’s because there’s money to be had if a product or service is made. Don’t give up on this platform yet. My big brain just arrived
 
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When a Kia stinger blows a head gasket which head blows first, driver or passenger?
I don't think it's common enough to generalize...most of the references I've found are secondhand rumor and hearsay.

Ported turbo manifold
Just this alone, if it can be replicated without a zillion hours of work, would be huge. There are a couple full kits with replacement manifolds and relocated big turbos, but they're very expensive and require a ton of supporting work.

Removing the bottleneck that chokes the stock turbos near redline would make pure/super stockers (upgraded CHRAs in stock housings) a more effective upgrade.

I think a lot more people would be interested in 600 hp and a 2000 rpm spool for $5k in a weekend, than 900-1000 hp and a 4000 rpm spool for $15k with the car down for a month.
 
I don't think it's common enough to generalize...most of the references I've found are secondhand rumor and hearsay.


Just this alone, if it can be replicated without a zillion hours of work, would be huge. There are a couple full kits with replacement manifolds and relocated big turbos, but they're very expensive and require a ton of supporting work.

Removing the bottleneck that chokes the stock turbos near redline would make pure/super stockers (upgraded CHRAs in stock housings) a more effective upgrade.

I think a lot more people would be interested in 600 hp and a 2000 rpm spool for $5k in a weekend, than 900-1000 hp and a 4000 rpm spool for $15k with the car down for a month.
Exactly, this is my thought process. I hope to be able to make this a service.

Anyway the company I wanted to get it flow bench tested with is swamped with work so no flow bench testing. I’m going to make the cut tonight and we’ll have to be happy with before and after results via caliper measurements and dyno measurements (later on)
 
Okay good news and bad news.

I cut open the manifold and it’s larger than 1 quarter and doesn’t neck down at all around the bend ( maybe a tiny bit at the end) honestly it’s a good design just small.

I measured the opening around the bend at 32mm.

The thickness of the manifold material is 5mm at the thinnest point.

Porting the manifold by cutting it open like I did and removing 2mm uniformly would gain us 36mm

The waste gate opening is 20mm and that’s extremely small.

The waste gate door is 30mm. I will port the wastegate door as large as I can get it. This will lower back pressure and increase hp between the 2 manifolds.

I’m afraid my research on this topic won’t net much gains for the amount of work involved. Maybe 20-40whp max

Attached are my photos.
 

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That's interesting. Tork's video claimed that a quarter (24mm or just under 1") wouldn't pass through the manifold, but from his video that might be at a point slightly closer to the turbo housing than at the bend where you measured (picture below is where he points when he mentions this). He does also mention a 1.1-1.2" opening, which would be 28-30mm, but even that should let a quarter pass.


1734147162627.webp

In your picture, is the small circle at the bottom right the exit from the manifold into the housing? Or is that just the wastegate port?

1734147241172.webp
 
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From interior to exterior to high performance - everything you need for your Stinger awaits you...
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