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what is that? haha
 

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There's only one stupid thing about that setup... The wastegate ports. Why does everyone insist on short cutting this piping?

Proper wastegate ports should Y smoothly from the manifold runners. Mine is done poorly, and so are just about everyone else's. I haven't seen a boostlogic manifold yet, but I wonder if they overlooked this as well.

Any time a fluid has to make 90° turns, bad things happen. Does anyone know why this is overlooked so often?
 

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Discussion Starter · #6 · (Edited)
There's only one stupid thing about that setup... The wastegate ports. Why does everyone insist on short cutting this piping?

Proper wastegate ports should Y smoothly from the manifold runners. Mine is done poorly, and so are just about everyone else's. I haven't seen a boostlogic manifold yet, but I wonder if they overlooked this as well.

Any time a fluid has to make 90° turns, bad things happen. Does anyone know why this is overlooked so often?
What for it is necessary? It is absolutely unnecessary thing for a turbo manifold. The basic stream of gases should go without resistance on turbo, instead of on a gate! )))

Show something better it?

I think that product from BoostLogic has to put it mildly a rest in comparison with this gadget ;)
May be only same from Full-Race. But it hav'nt so long runners.
You can compare http://www.full-race.com/catalog/product_info.php?products_id=1052
 

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Ideally, the wastegate port should be going along with the direction of exhaust flow; however, it can be easily compensated with a much larger wastegate, if not, two large wastegates :)

As long as you have two nicely sized wastegates, it will compensate for just about any weird direction changes or lengthly wastegate inlet pipe. On our 2JZ's, it's not a big concern until you reach really high RPM's and really large turbos (9000+ RPM and big power). If the turbo is conservatively sized, with a smaller A/R for better spool up (e.g. T4 0.82 A/R), it will defintely reduce any chance for boost creep or uncontrollable spikes.

I really like the manifold, and in fact, I recently built myself a similar looking manifold...lol Lots of runner length, but mine has a few special tweaks to it. Mine was purposely done NOT to be equal length to compensate for a few known trouble cylinders on the 2JZ-GTE.

This manifold is nice... Any good pics of the merge collector?
 

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Ideally, the wastegate port should be going along with the direction of exhaust flow; however, it can be easily compensated with a much larger wastegate, if not, two large wastegates :)

As long as you have two nicely sized wastegates, it will compensate for just about any weird direction changes or lengthly wastegate inlet pipe. On our 2JZ's, it's not a big concern until you reach really high RPM's and really large turbos (9000+ RPM and big power). If the turbo is conservatively sized, with a smaller A/R for better spool up (e.g. T4 0.82 A/R), it will defintely reduce any chance for boost creep or uncontrollable spikes.

I really like the manifold, and in fact, I recently built myself a similar looking manifold...lol Lots of runner length, but mine has a few special tweaks to it. Mine was purposely done NOT to be equal length to compensate for a few known trouble cylinders on the 2JZ-GTE.

This manifold is nice... Any good pics of the merge collector?
This, I run a 60mm wastegate because it is easier for my exhaust to flow through the turbo then the wastegate. I had a tial 44 and I had problems keeping the boost down.
 

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Discussion Starter · #10 ·
Any good pics of the merge collector?
You about merge dump-pipes to down-pipe?
No, there is no any space for this purposes, i think to flow waste to fender with chromed rings and i'll make an inscription "Don't touch! It's too HOT!" :lol:

Well, this is custom work, maestro did all runners max long for best low range torque.
It has very good results with this decision. He said for comparison that i'll get same torque with CR 8.0 + his manifold as CR 10.5 + hks-like manifold.
I known more than 10 projects with SOARA's manifold and all guys very happy.
 

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Fab work looks clean. I'm unclear on how the longer runners will increase torque at low rpm with turbo though. If you consider that the turbine wheel has a mass, and that air pressure provides the torque to accelerate that mass... a higher pressure before the turbine wheel means more torque available to spin the turbine wheel. And one way to have higher pressure in the manifold is to have a manifold with shorter runners or something more akin to a log style.

Look up articles on turbine pressure ratio, or expansion ratio...

Here are some real world comparisons of log vs. tubular albeit most of these tests still have some flaws.

http://www.full-race.com/articles/sr20_turbo_manifold_test_writeup.pdf

http://www.full-race.com/articles/1.8T_turbo_manifold_test_writeup.pdf

I think the benefits of increased torque come more from the twin scroll housing, less pulse interference, etc.. and I wouldn't expect it to have more torque than a log style with twin scroll at low rpm.

Mid-High rpm - your nice manifold all the way for torque and horsepower though.


Regarding poorly designed wastegates, I agree most designs are not optimal! I think it's just a design/packaging/manufacturing compromise... you can get accurate enough that most people will never notice or need ultimate accuracy with sub-optimal designs. Something like HKS 2JZGTE Supra manifold has a good design... If you're trying to squeeze out every bit of power you can repeatably, and you can't afford even the mildest boost inconsistency, it's definitely worth more time.
 

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You about merge dump-pipes to down-pipe?
No no, I mean the merge where all 6 runner meet to the turbine flange.. I know it's twin scroll, so it would be dual 3-into-1 collectors. There is one pic of the T4 flange, but it's kinda dark and can't see much of the inside... :)

Hoping to see some brighter pics of the inside of your merge collectors... For example, here's the one off my Supra with the camera flash on:

 
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