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2530's are not the turbo.

You want GT-SS's, the smaller ones - if you go twins.

Or a 3076 .82, both will see you around 330rwkw give/take.

which one will give response? GT-SS or the GT3076r .82?

will GT-SS produce 350RWKW without a strugle?

Can i use GT3076R .63 rear for more response?

Well you said close to 350rwkw, 330rwkw is close in my book. GT-SS's and a GT3076 are similar in output and both should be making 330rwkw on around 20psi.

Every motor is different as is the build, and they are all factors.

Which is more responsive is always arguable, the never ending debate of twin vs single will forever go on :P

IMO both will be very similar. GT-SS's have room for i believe a tad more top end, the 3076 a tad more response. However do not take that as signifigant either way. You aren't talking 1000rpm repsonse or 50rwkw extra (for example). It'll be a smidge either way

A .63 rear will limit you to under the 300kw marker, that is not a wise choice in my book given what you want.

I think the major concerns here are how much of either system you have now and how complex the system is later .

The fact that you have the GT3076R and a waste gate means you're a manifold and dump pipe short of a single system .

Should you decide you want to play around with things afterwards the single system would be cheaper and easier because theres one of everything and most of it is easy to get at .

If you were only going to pull it down once and you knew your turbo choice was going to be correct forever for you then maybe the twins would be the go .

"Response" is subjective because so much depends on the spec and condition of the engine as well as how well its tuned .

Personally I'd be trying to get the engine build/spec the best it can be for what you want and add turbo/s as the afterthought .

I don't know why but at times people like to think that there is some mythical magic turbocharger that is going to be supremely powerful everywhere and its not the case .

The bottom line is you can't have boost at low revs and expect it not to run out of gas flow and choke off in the upper rev ranges . The problem is that GTRs are heavy cars and the low compression ratio 2558cc engine doesn't make sufficient torque at low revs to lug it around like say a 4+ litre V8 could .

Turbocharging works but the limited capacity/mass means you need some revs to get it happening .

In short , needs 3L so the engine can do more lugging before boost is made . For anything less size the turbos so the engine makes torque where its needed and accept it won't do moonshot revs .

Also from what I've seen with single GT3582Rs and externals on RB26's you may need to rethink the 44mm gate .

One fella I know found that once he put a free flowing 3 1/2" exhaust on his car the 44mm waste gate no longer coped and he had to have a 50mm one fitted to his 6Boost manifold .

Your call but big pipes behind turbos at the front of the exhaust system is a must to have it spin up as soon as possible .

My old L Series subaru made a huge difference when its turbo outlet pipe was changed to 3" and this is a turbo Garret rates at 260 Hp - 47mm turbine outlet hole . I would want a minimum of 3 1/2' if at all possible out of a GT3076R , it can step down in stages further back when the gas has cooled and "contracted" and you can do the muffling at whatever size you want back there . Very little if any sound penalty when the pipes are hugeish at the front only . Makes a significant difference turbine response and engine power wise .

More coffee now , cheers A .

I think the major concerns here are how much of either system you have now and how complex the system is later .

The fact that you have the GT3076R and a waste gate means you're a manifold and dump pipe short of a single system .

Should you decide you want to play around with things afterwards the single system would be cheaper and easier because theres one of everything and most of it is easy to get at .

I was under the impression that the twin's would be bolt on (well. fiddle, curse, and bolt, on. but bolt on none the less)

Well you said close to 350rwkw, 330rwkw is close in my book. GT-SS's and a GT3076 are similar in output and both should be making 330rwkw on around 20psi.

Every motor is different as is the build, and they are all factors.

Which is more responsive is always arguable, the never ending debate of twin vs single will forever go on :P

IMO both will be very similar. GT-SS's have room for i believe a tad more top end, the 3076 a tad more response. However do not take that as signifigant either way. You aren't talking 1000rpm repsonse or 50rwkw extra (for example). It'll be a smidge either way

A .63 rear will limit you to under the 300kw marker, that is not a wise choice in my book given what you want.

tnx for the info. im gonna go along with GT-SS & dont wanna pass 350rwkw mark as only got 264 cams and factory internals. im happy with 300-330kw. cheers sam

Edited by newlife
I think the major concerns here are how much of either system you have now and how complex the system is later .

The fact that you have the GT3076R and a waste gate means you're a manifold and dump pipe short of a single system .

Should you decide you want to play around with things afterwards the single system would be cheaper and easier because theres one of everything and most of it is easy to get at .

If you were only going to pull it down once and you knew your turbo choice was going to be correct forever for you then maybe the twins would be the go .

"Response" is subjective because so much depends on the spec and condition of the engine as well as how well its tuned .

Personally I'd be trying to get the engine build/spec the best it can be for what you want and add turbo/s as the afterthought .

I don't know why but at times people like to think that there is some mythical magic turbocharger that is going to be supremely powerful everywhere and its not the case .

The bottom line is you can't have boost at low revs and expect it not to run out of gas flow and choke off in the upper rev ranges . The problem is that GTRs are heavy cars and the low compression ratio 2558cc engine doesn't make sufficient torque at low revs to lug it around like say a 4+ litre V8 could .

Turbocharging works but the limited capacity/mass means you need some revs to get it happening .

In short , needs 3L so the engine can do more lugging before boost is made . For anything less size the turbos so the engine makes torque where its needed and accept it won't do moonshot revs .

Also from what I've seen with single GT3582Rs and externals on RB26's you may need to rethink the 44mm gate .

One fella I know found that once he put a free flowing 3 1/2" exhaust on his car the 44mm waste gate no longer coped and he had to have a 50mm one fitted to his 6Boost manifold .

Your call but big pipes behind turbos at the front of the exhaust system is a must to have it spin up as soon as possible .

My old L Series subaru made a huge difference when its turbo outlet pipe was changed to 3" and this is a turbo Garret rates at 260 Hp - 47mm turbine outlet hole . I would want a minimum of 3 1/2' if at all possible out of a GT3076R , it can step down in stages further back when the gas has cooled and "contracted" and you can do the muffling at whatever size you want back there . Very little if any sound penalty when the pipes are hugeish at the front only . Makes a significant difference turbine response and engine power wise .

More coffee now , cheers A .

tnx for genuine advice mate. gonna go with twins. i was worring about the size of the waste gate as well. i think twins would be the go. cheers sam

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