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Hey guys,

Just after a bit of advice for a turbo upgrade on an rb20. Looking at either a KKR 430 or Garrett 2871. I know the KKR is about half the price of the 2871, just wondering if it would be worth spending the extra on the 2871.

Will have the normal mods, 550cc injectors, 040 pump, front mount, full 3" zorst, PFC or similar, intake, etc.

Just after a bit of advice on what to do.

Cheers

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best bang for buck is probably an RB25 turbo. past that maybe an HKS 2530 or similar.

yeah already have a rb25 turbo, looking for a fair bit bigger, high mount set up. Looking for 220-250kw...

From memory the 2871 doesn't come in a t3 flange only a t2 which means you will need an adapter plate from t2 to t3 which is a little bit more stuffing around

Better off going a GT28RS, GT2530 or even a GT2535 which is slightly larger

Since your going the bigger injectors, stand-alone ECU etc etc I probably wouldn't go with an RB25 turbo, something bigger and that will make more power will be better suitable

If your looking for a budget upgrade, something up to about 190rwkw then go the RB25 turbo

From memory the 2871 doesn't come in a t3 flange only a t2 which means you will need an adapter plate from t2 to t3 which is a little bit more stuffing around

Better off going a GT28RS, GT2530 or even a GT2535 which is slightly larger

Since your going the bigger injectors, stand-alone ECU etc etc I probably wouldn't go with an RB25 turbo, something bigger and that will make more power will be better suitable

If your looking for a budget upgrade, something up to about 190rwkw then go the RB25 turbo

Horsepowerinabox.com have just brought out a GT2871 with t3 flange and rb20/rb25 six bolt dump pipe flange, for a direct bolt on fit, which is the turbo im looking at, bit exe tho at $1850...

If you are going high mount then don't worry about the flange on the turbo...you can get a high mount manifold with a t2 flange if need be...dump pipe will most likely need to be custom anyway also so i wouldn't worry about that...

However...there is no point in high mounting a kkr430 or even the 2871...keep it low mount if these are your choices...

you can get your rb25 rear housing machined to suit the 2871 and bolt up instandard position.

if you're going highmount, go big if you're going a 2871 or kkr go low and keep it lookin standard.

also internally gated turbo highmounted = very gay imo

wats kkr???? :D

im also looking at options for a bigger turbo udgrade in the future. the T2 flange means you cant bolt the turbo onto the RB20 ex mainifold?

sorry not too sure about this stuff :nyaanyaa:

Yep T2 flange means no for RB20/25

You need a T3 flanged turbo to bolt on to the standard manifold

KKR turbos: http://www.otomoto.com.au/kkr/turbos/index.html

It goes against the grain but possibly a GT2860RS or a GT2871R in a reprofiled RB25 turbine housing would be reasonably easy and cost effective .

Someone on this forum a while back had a non IW real GT3071R on an RB20 and he felt it was ok though these days you'd used the GT30 0.63 A/R IW housing for convenience sake . Its a fair bit of turbo for a 2L six so may be a bit laggy for some .

A .

cheers abu,

i heard that most turbo's up from the RB25 hi flow wont spool up quick enough. When buying a turbo for the RB20 how u can tell if it will spool up fast enough?

Well...you search...because too many of us had the same question as you and there are heaps of threads about this already...

the reality is, if you want 220 + rwkw, you're going to have lag, an RB20 needs at least 4000 rpm on board to start pulling. some like this, some dont, if you dont then stick with 200 rwkw and run a smaller turbo which will give you more midrange punch for the sake of 20-30 rwkw up top

the reality is, if you want 220 + rwkw, you're going to have lag, an RB20 needs at least 4000 rpm on board to start pulling. some like this, some dont, if you dont then stick with 200 rwkw and run a smaller turbo which will give you more midrange punch for the sake of 20-30 rwkw up top

lag = fine, as long as it makes the power at some revs i dont mind, 3071r is looking the goods. Cams be a good investment if i was going to run a turbo like that?

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