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IMHO the 3071 w genuine housing is definately the best turbo choice for an RB25 in the current climate (2835 being number 1 but cost prohibitive these days)

BUT..........

if i had my time again i would be going a twin scroll 3076 with a 6 boost manifold and GTR plenum

I thought the consensus from discopotato was that the twin scroll didnt have a big effect on 6 cylinder engines, more 4 cylinders.

The 6 boost manifold is probably a bit separate as it would help all of the turbos we are discussing.

If you plot your current turbo against the 3076 you have more area under the curve.

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hence the twin scrol idea.... i thought it would get me a little more under the curve but not much, hence why i wouldn't change over to that setup, it's just what i'd look at doing if i had my time again :P

actually if i had my time again, i'd probably have just done an LS3 conversion

yeah the reason disco said twin scroll is more suited for 4 cyl is because the firing order and the engine is optimized to suit the firing order

like the 4g63 and sr20 are more suited for twin scroll as the firing order matches the manifold split setup

i wonder how complicated a properly twin scroll manifold on a rb20/25/26/30 footprint would look

and perform with a properl twin scroll manifold with the correct firing order match and turbo to suit

Twin turbo does not follow the firing order (in terms of GTR), where twin scroll is meant to given the parted collector/rear housing

difference - who knows, maybe a few hundred RPM?

You aren't talking 1000's of RPM of response either way.

I got 254kw at 3200rpm with r33 gcg high flow turbo. Im very happy with the response and power i have with this turbo. I only paid $850 for gcg from SAU forums and sold my stock turbo for $300. So only cost me $550. i still retain factory air box and car looks very stealth. Best bang for buck turbo.

I know of people on this forum who have run 12.3s quarters with this power on semi slick street tyres.

Invest in some mickey thompson full race slicks on 15inch chaser rims and a jim berry full monty race clutch and you will run 11s with around 250kw.

Its not always about all out power. Many other factors to consider...

hey mate 254 RWKW yeh? if so thats not bad at all for a highflow especially for that price!, what injectors do you use? also how much did you get charged for installing the new highflow turbo, did it need anything different to fit it or did it slot straight in like before?

sorry for the hundreds of questions.. but with my wage, id much rather 254rwkw for $850 or $550, as opposed to 300rwkw for $3000

cheers.

Twin turbo does not follow the firing order (in terms of GTR), where twin scroll is meant to given the parted collector/rear housing

difference - who knows, maybe a few hundred RPM?

I'm not sure what you mean by that? The front 3 and rear 3 alternate so with twins each manifold collects the same as a properly designed twin scroll manifold...

hey mate 254 RWKW yeh? if so thats not bad at all for a highflow especially for that price!, what injectors do you use? also how much did you get charged for installing the new highflow turbo, did it need anything different to fit it or did it slot straight in like before?

sorry for the hundreds of questions.. but with my wage, id much rather 254rwkw for $850 or $550, as opposed to 300rwkw for $3000

cheers.

I sourced most of my parts from SAU second hand from good honest people, thats why i love this site..spread the love.

Paid $850 for GCG high flow only 2 years old checked by gcg , sold my stocker for $300 so cost me $550 and installed it my self, piss easy took about 5 hours and everything bolted straight back on. True direct bolton , nothing to change. If i can do it , any one can.

Apexi power fc=$950 second hand SAU

Nismo 550injec=$600 second hand SAU( need injectors to max out turbo potential)

Bosch 040 in tank fuel pump=$50 second hand SAU(needed to meet fuel demands)

Splitfire coils=$450 second hand SAU(needed to run bigger gap on my plugs, went from .7 to 1.1 coppers when i upgraded coils.

JJR return flow coooler=$450 new

3 inch exhaust turbo back full stainless=$650 wreckers

Greddy profec b EBC

Run stock air box.

Tune=$750 unigroup engineering

My set up is begging for a garrett gt3071 or 76r bolton replacement and retune but this exercise will cost me between $2500 to $3000 , to gain an extra 30kw atw on my current set up. The only way i would justify this would be to take a ride in a gtst making 280kw + . If blown away by the difference then i would do it.

For now im at peace with what i have.

Hope i helped.

No offense - do you know how to read a dyno sheet?

You have 254rwkw @ 6750rpm. Not 3200rpm.

You have ~135rwkw @ 3200rpm

You also have boost control issues.

I stand corrected

Thankyou for teaching me to read a dyno, thats why i love this site, you never stop learning

What i should have said is that you will have full boost 16 to 18psi by around 3200rpm with this turbo

Thanks.

I'm not sure what you mean by that? The front 3 and rear 3 alternate so with twins each manifold collects the same as a properly designed twin scroll manifold...

Cool, yeah I was scratching my head but didnt have the knowledge to go against the president haha

So it seems a big waste to go to all the effort of twin scroll on an RB20/25 when an RB26 with twin turbos already has everything done from the factory.

So is this the major reason that twin turbos on an RB26 will have more low down power/torque then the equivalent sized single turbo conversion?

The only way i would justify this would be to take a ride in a gtst making 280kw + . If blown away by the difference then i would do it.

where you live?

i'm happy to er... "help" :(

Hey guys, similar question i thought you may be able to answer:

One turbo, running in a 220kw tune (injector and afm limited), vs the same setup, but with injectors and obviously a bit more boost (profec b) for 270kw.

Obviously off boost performance is identical, and full boost performance is waaay better, but what's the "in between" area like?

I used to have an MR2 years ago, and when boost was turned down, it was linear and boring, and with boost up, it was epic fun, but felt like it had a shitload more midrange. So i'm wondering, when i get injectors and a tune, is it likely to be a lot more midrange, or just top end stuff, it's a really laggy turbo i can't afford to replace yet (KKR560). I'd imagine it would seem more "responsive" as the wastegate would stay shut for longer before hitting full boost?

I'm just poor at the moment, but think i can afford injectors and a tune by the end of the year, as a present to myself, and want to make sure that the performance jump is as epic as i am expecting it to be :( Gavin Woods will be doing the tune, as he's a champion :(

Hey guys, similar question i thought you may be able to answer:

One turbo, running in a 220kw tune (injector and afm limited), vs the same setup, but with injectors and obviously a bit more boost (profec b) for 270kw.

Obviously off boost performance is identical, and full boost performance is waaay better, but what's the "in between" area like?

I used to have an MR2 years ago, and when boost was turned down, it was linear and boring, and with boost up, it was epic fun, but felt like it had a shitload more midrange. So i'm wondering, when i get injectors and a tune, is it likely to be a lot more midrange, or just top end stuff, it's a really laggy turbo i can't afford to replace yet (KKR560). I'd imagine it would seem more "responsive" as the wastegate would stay shut for longer before hitting full boost?

I'm just poor at the moment, but think i can afford injectors and a tune by the end of the year, as a present to myself, and want to make sure that the performance jump is as epic as i am expecting it to be :( Gavin Woods will be doing the tune, as he's a champion :(

Midrange will jump mainly but you will still get a nice top end bump.

Midrange is where its at anyway, how often do you hit 7000 revs?

So it seems a big waste to go to all the effort of twin scroll on an RB20/25 when an RB26 with twin turbos already has everything done from the factory.

So is this the major reason that twin turbos on an RB26 will have more low down power/torque then the equivalent sized single turbo conversion?

Equivalent sized SINGLE ENTRY single turbo, yes - and no its not a waste on a 20/25 as you only have to buy one turbo etc... imho. You have far more choice with single turbos, less plumbing, etc. Try working on a Skyline with a big single versus low mount twins haha.

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