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Hey guys.

I have recently done a rb20 s13 conversion. All i need is stadard rb20 cooler piping and new front-half exhaust.

I have a t4/3 hybrid (from a vl) with the dump pipe to suit, I stupidly did not notice now that i have the turbo on, when i put the dump pipe on it goes straight into the side of the tunnel.

This is due to the angle on the rb20 exhaust manifold(instead of sitting parrallel like rb30). Does anyone know if I could get the rb20 standard dump pipe and attach it (keeping in mind that the vl t3 has the wastegate flap built into the dump pipe).

Or am i going to have to go for a custom job. which will cost me an arm and a leg...

Below is a pos picture i drew... this suppose to be a view from the back of the engine (if you poked your head through the passenger side firewall)

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https://www.sau.com.au/forums/topic/36144-rb20-exhuast-manifold-question/
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I think you may find that a VL turbo will be a tad laggy on an RB20 (not 100%), but it is designed for an engine 50% larger than the one you have, and the 3L has mountains more torque too. Wouldnt it be easier to get a Rb25 turbo, or RB20 turbo and use that instead? or can you change the turbine housing?

Not too familiar with the T3, but I know the wastegate setup you talk of, and it is pretty ordinary - definately no rocket science there.

RB20 & RB25 are both t3...

I know the tubo will be laggy. But it will deliver up top.

My main question is are the rb20 standard turbos boolted on an angle....

Look @ this pic. rb20 and rb30 side by side from a passenger seat view.

exhaust.JPG

Is this picture correct. As you see the green lines they are a indication of where the dump pipe will go. Now.... on the rb20 see how the dump goes sideways?... i want to know if a stanard dump will drop straight down? Because at the moment it goes into the firewall...which aint cool

Is it possible to to cut off the vl dump and have it machined flat and then mount it as a sandwich plate between the back of the turbo and the rb20 dump?

The only thing i can see being a problem is that you would need new longer studs in the turbo housing to suit the wider plate/dump arrangement and need an additional gasket.

It'd also be a lot neater than some of the nasty cut and shut jobs ive seen people do in this situation, and it gives you the option of upgrading to a better off the shelf dump/front pipe arrangement in the future.

sorry Niz, cant help. The RB25 turbo sits with the wastegate and turbine outlet in a vertical arrangement - I was under the impressoin that stock RB20 was the same, but never looked that closely at one.

For your info, the RB20 and RB25 are not T3 turbos, just have a T3 flange where they joint the manifold.

good luck

Oh sweet it was you then just got a couple of Q's about it./

I bought one a couple of weeks ago wont go into it, But a whole lot of stuffing around later it was as useful as well, Something pretty F***ing useless. (never again with second hand)

But anyways I have ordered a new GT Pro 2way Nismo LSD. Now a friend just recieved his and After the initial "bedding" in process was complete, The diff seemed to operate fine

Was set on it's softest setting, Then it went from chirping (like a locker) on tight turns, Carparks etc to really rough "clunking". with about 2 weeks or so from chirps to clunks.

Now surely this is not normal...is it?

Only thing i can think of is that maybe it only operates "properly" on the tighter settings as the clunks sound like something is loose or broken, However wont these tighter settings pretty much turn it into a locked diff (more or less). If so why did i spend X amount on this diff when i could have bought a second hand center and welded it up for like 10% of the cost???

You can get hold of full 3" dump / front pipe units for around $250. If you care to wait a couple of weeks, I will have a cast dump available after I have a 3" unit made up for my RB20DET.

Steve, NIZ

The RB20 turbo is the same orientation as the RB25.

NIZ, you might be able to rotate the exhaust housing to suit, but it may interfere with the actuation of the wastegate.

NIZ, you might be able to rotate the exhaust housing to suit, but it may interfere with the actuation of the wastegate.

? How so?

The exhaust housing has to sit at the same orientation as it's bolted to the exhaust manifold, all you'll do is rotate the core and comp housing in relation to the rest of the engine and then nothing will line up

My RB20 turbo has a 6-bolt flange holding the exhaust housing to the core. Loosen those bolts, the housing can rotate in relation to the core, then tighten the bolts again.

Obviously the RB30 turbo isn't constructed the same as the RB20 turbo.

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