Zero R

iTrader: (1)

https://www.rx7club.com/showthread.p...0&pagenumber=2

zyounker

Yeah i posted a thread about ATP and the T4 foot print awhile ago..


You could do a GT35/40 setup for under $2K it looked like.

Zero R

iTrader: (1)

I assume you mean with the crap manifold.

zyounker

No the HKS Cast.. Which i dont consider crap.. It is not the best but if you are looking for a reliable manifold it is a good low cost choice HKS Cast is the only one i know of.


But either way, if you can use a T4 footprinted GT35R then you can put it on most T4 manifolds as long as there is clearance between the LIM and the turbo.

H2o

yeah but then your stuck with a .84 housing.

H2o

.

Zero R

iTrader: (1)

Ted, you are wrong on this one sorry, flow to the wastegate is just fine and shared evenly with the turbo, the inlets to the wastegate are also close the turbine entry as well, I do believe that it was written it should be that way somewhere?

RETed

Okay, I just looked the link at the top of this page, and it looks like the manifold got reworked (AGAIN).

It's a decent design, and the only thing I question is the really short runner length from exhaust port to turbo inlet.

I still think our FC design is better.

http://rx7cz.net/photos/workshop70/


-Ted

Broken09

iTrader: (1)

Isn't that somewhat of a partial opinion since it's your design? Or am I misreading what you're writing. In general people will prefer their own design. I'm not saying yours or Sean's is better technically that can only be proven through testing.

RETed

It depends how you look at it?

I know the FD has a lot less clearances.
I believe our measurements was 9.25" from exhaust port to engine frame rail for FD, 10.5" for FC.

I mean this can't be the end-all design for a GT35 + 13B-REW + FD3S...that's my point.


-Ted

Broken09

iTrader: (1)

True, but at the same time to truely be able to back any of this theory or opinion up it'd take testing of both setups on the same car..... until then it's all theory.
-Nic

Zero R

iTrader: (1)

My first prototype was almot identical to yours, what I changed was the angle, I noticed better response from the turbo when the flow favored the turbo slightly(obviously), I also had to change it because I was just getting my 40R's in and needed a dual wastegate runner setup for the divided version. I have another manifold I'm finishing up on I'll get pics up when done.

-Sean

Zero R

iTrader: (1)

To be fair you can't say it's not no more than I can say it is. We have rules guidlines setup from where we start and then we stay in there, and get the best compromise period, that's all you can do.

RETed

Sure, and we are basically grounding are positions on these guidelines.

Unless we're going to back everything with empirical data, we end up arguing on these guidelines.

I can turn around your point and how can you qualify your statements about the "crap manifold"?

I think we can all agree that smooth, large-radius bends are best for (exhaust) gas flow.

We may argue about the best runner length (I've been told 20").

We may argue single WG runner versus dual WG runner.

We may argue on passage diameter.

We may argue on turbo placement.

We may argue on WG placement.

So where does it leave us?
Basically back on square one - without proper measuring and testing, we can't argue either way.

Personally, I don't like the dual WG runners, because I'm sure there's some weird reversion going on in those runners...

You're right; I can't prove it.


-Ted

Zero R

iTrader: (1)

The crap manifold is easy to explain I'm not saying the design is crap it's buld quality is garbage, thin walled stainless, like sheet metal thin, flanges are way too thin, and once reworked by"XXXX" they are using garbage rod, weld splatter everywhere and not all the welds are strengthened due to not being able get the mig welder in there. We both know they are crap, as for reversion, they are slightly offset to help, and duals are not bad when you run dual all the way to the gate itself I'll find a pic of it. I'm not fully on the boat with the reversion through the dual setup thing, but understand the why.

And by rules and guidlines I wasn't just refering to the things mentioned above but also, how else can this be used in other applications?(ie other turbo's fitment, will I be able to keep the AC, blah, blah blah, you get the point. Like I said I never knocked where yours is at I had almost the same exact setup made and jigged, just other constraints made me go this way.

-Sean

Broken09

iTrader: (1)

Ted,
Just something I've been thinking about the last couple of hours but how would reversion be present in dual
wastegate runners but not present in a single shared runner, guess I'm a bit confused....
-Nic

RETed

There is still going to be reversion in the system due to the two exhaust ports, unless you design some kinda collector (which we know isn't the best design in terms of an efficient turbo exhaust manifold design).

The reversion I was talking about is in the wastegate passages.  Since our single wastegate path is taken after the two main pipes are joined, there is little or no chance of reversion in the wastegate passage.  The A-spec manifold pictured above takes it's dual WG pipes prior to the collected point, and thus subject to reversion.  The reversion takes place in the collected joint closer to the WG.


-Ted

Broken09

iTrader: (1)

ah ok

Broken09

iTrader: (1)

Ok Ted,
I've got yet another question I've been throwing around over the past few hours. So if there is still reversion in both manifolds, why is one reversion better or worse than the other?
I'm just trying to understand this whole concept a bit better.
-Nic

RETed

Reversion closer to the wastegate could cause the wastegate to flutter due to the pulsing.

If we shift the reversion away from the wastegate valve, the wastegate pipe(s) act as a buffer.

Now, I can't prove this is so, so please let's not turn this into debate about testing results.  Yes, it is all theoretical.


-Ted

Broken09

iTrader: (1)

No no debate from me this time just wanted a theoretical explanation. So my next question is the theoretical shift in the reversion could this have some sort of adverse affect on the turbo in one place more than if it were in another, therefore affecting flow?

Broken09

iTrader: (1)

And yes I'm quite aware that at this point you're probably thinking are these questions ever going to stop from this guy.....

RETed

Oh, I'm sure it does...
So that brings up the million dollar question - where to put the merge that will least affect performance or give you best gain in performance.

If I knew that I'd be rich!


-Ted

Zero R

iTrader: (1)

I can say confidently that, I have no issues with wastegate control and this manifold, it holds rock solid and doesn't spike.

-Sean

Jetlag

Cheap *** here again. So the HKS cast manifold is a divided manifold right? But that will be of no benifit to with the T3 foot print right?
I use to have a custom SS manifold setup with 60-1 T04. I was happy with it, until I took a ride in my friend's FD with the GT3540.
After that, my turbo seems really laggy. This is why, I've decided to go with this turbo and manifold combo.