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I've modified that rear housing alittle since tuner mentioned it was too hot. Should have more chance of hitting 300rwkws now with a larger turbine housing. Just depending on how hard he wants to push the car.

just got a call...

car went 340hubber hp (253kw) on 1.5bar (no dyno correction)

standard rb20det

gtr injectors

z32 afm

atr43g3 0.63 on standard manifold

will get a graph up tomorrow

Edited by Cerbera

I need my brain looked at, we were looking at the graphs trying to work out why the car had a wierd curve (laggy and not making enough top end power)

Worked out I had f**ked setting the cam gears, will get them set again (they are 4deg out on inlet and 8 out exhaust) and hopefully retuned later in the week

Stao, he didn't need to... Was holding boost at pretty much any level through out the revs. Hoping for at least 30odd hp with the cam gears fixed and a whole lot more response. Can't believe i made such a stupid error haha

Edited by Cerbera

Some updates. I've made a new type custom turbine wheel aimed for power incensement with OEM turbine housings. Its expected to gain HP by roughly 10%。 Let me know if you are interested to try them out. I will pay for your tune at Dr.drift. You must have a fully working car with all supporting mods including ECU, injectors, Z32 AFM, 3inch turbo back exhaust and a metal intake pipe.

Also I want to make a note for people who's currently running this type of split dump pipes:

shitdump2.jpg

First of all the divider isolates the internal gate area which the gate flap does not open to a full 90 degrees. This result boost creep issues.

Diagram not up to scale, just give you a basic idea of what happens.

wastegate.JPG

2ndly the inner diameter is 2.3 inches with the split pipe plumbed back. Factory dump has 2.5 inches inner diameter. In another word factory dump would flow better then above, it will create exhaust flow restrictions resulting high back pressure and high exhaust manifold temperture affecting overall power output. For the best results please run a 3inch turbo back pipe or a bell mouth dump with 3inch front pipe.

Tthe divider isolates the internal gate area which the gate flap does not open to a full 90 degrees. This result boost creep issues.

2ndly the inner diameter is 2.3 inches with the split pipe plumbed back. Factory dump has 2.5 inches inner diameter. In another word factory dump would flow better then above, it will create exhaust flow restriction, Please do run a 3inch turbo back pipe or a bell mouth dump with 3inch front pipe for high performance applications.

What you have posted above is totally incorrect. That product works fine, there is no exhaust restriction in the way you describe at all.

Also as the wastegate gases have been split off, the WG pipe does not need to be as big as the dump pipe.

As you can see from here:

post-34587-1276873030_thumb.jpg

The Skyline turbo wastegate flapper does not open the way you have shown in your diagram at all. (R33 & R34 are identical)

The flapper opes to a perpendicular end, rather than a parrallel one as your little diagram has shown...

As a turbo retailer... I'm shocked. :)

Edited by GTR_RB26TT

That was just a basic diagram so every one can understand what happens in there. Diagram is not upto scale.

A 2.3inch pipe does not flow any better then a 2.5 or 3 inch pipe. Simple as that.

Does not matter what it is, fact is the diagram couldn't be more wrong if you tried.

What you are saying occurs, and what actually occurs are two different things unfortunately and misleading/incorrect.

The wastegate flapper is not impeaded at all, that is cold hard fact.

Users are being mislead by that diagram - you should delete it.

Edited by GTR_RB26TT

I'm not going to argue with the interpretation. This issue have been arose before, This diagrams explain the very nature of the problem.

Of course you not - it cannot be argued and hence you have now removed the inaccurate information that should never have been posted in the first place.

The diagram you removed had zero impact on the situation, you would not have removed it if it were correct :D

Of course you not - it cannot be argued and hence you have now removed the inaccurate information that should never have been posted in the first place.

The diagram you removed had zero impact on the situation, you would not have removed it if it were correct :thumbsup:

Stao has a hell of a lot of cred around here and is very generous with his knowledge and time helping people on these forums. He is also an expert on turbo's with valid point and you are just an annoying, rude NOBODY. :D

I rarely post, however I do read a lot and have been playing with turbos for 10 years myself.

The diagram I was questioing has now been removed, so sadly, you do not even know what you are commenting on.

I am not for one second saying Hypergear does not know what is going on.

However at times some of the information provided is just straight up incorrect & wrong.

Something you would not expect from such an expert, last nights diagram was another prime example of this.

If you saw what was posted last night, you would have your heads in your hands as I did last night viewing it.

Although I'm not sure what specifics you two are arguing about, Stao is correct about those split dumps jamming the wastegate. I had one of those split dumps on my car and it actually ruined my actuator diaphragm, dangerously gave me unlimited boost too. I disconnected actuator and moved the wastegate flap by hand...it only had 45 degrees of movement and kept getting stuck on something, which I thought was the pipe divider/seperator. Removed that and it was still getting stuck...turns out the wastegate pipe wasn't lining up properly and wasn't big enough. I die grinded the shit out of it, short of breaching the welds that hold the pipe onto the flange...and only then did it open up to 80 degrees. This STILL gave me boost creep (I run standard 7psi boost). I ditched it and got a custom 3 inch bellmouth made up, never had a boost creep / overboosting problem again.

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