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As the subject states, i'd be interested in hearing from anyone using any form of upgraded turbo on their RB20.

I have heard so much positives and negatives about Hi-Flowing the standard turbo, fitting a VG30 and fitting a RB25 turbo that i am confused.

Can people who have actually done anything (even aftermarket turbos) please buy in to this argument and help me out.

I'd be very interested in some comments and results.

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Mr RB20

I am also interested in the same mods..... i ve herd that the VG30 turbo is a excelent and cheap upgrage for the RB20. but dont expect more than 190-200Kw @wheels. however rebuilding the VG30 (with a steel exhaust wheel) plus hi flow can get a little laggy, and will probly only make 200 -220 Kw @wheels... exactly how laggy i dont know ive spoken 2 a few performance places and know one can give me a straight answer.... does any one have any other info???

pm either inark or meggala, they've both done some work on their RB20DET's. meggala changed his RB20DE to a DET and inark is currently putting a VG30 turbo on i think.

Mr Rb20

I'd stay away from high flows of the stock turbo, unless you only want another 15-20rwkw. A series one R33 turbo will give you a bit of a increase, but you can only run 14psi due to the turbine wheel being ceramic.

After a lot of thinking i ended up getting a HKS 2510 turbo second hand. My goal was to have 200rwkw, with as little boost as possible, and still have almost stock drivability, and the 2510 fits the bill pretty well.

With my current setup - stock engine, tube and fin front mount cooler, Bosch motorsport pump and re-mapped stock computer, it made 198rwkw with 1bar boost on a warm summers day. The best part is that it drives very close to stock, just has a heap more top end.

The best part is that the turbo is still running lowish boost (for a HKS turbo) and has the ability to run 1.5 bar and make around 220-230rwkw with a revised fuel system.

Bolt on HKS turbos are awesome in my opinion, I'd recommend one if you want to upgrade

Chris

Thanks for all the replies.

I'm thinking now of upping the boost on the standard turbo to 16psi.

I have a front mount and exhaust so i hope this will be alright.

I am trying to eliminate some lag.

Chris - where does the boost start to kick in on the HKS and when does it hit full boost and till what revs ??

HKS bolt-on seems like a good idea although the VG30 is still very tempting.

Anyone in SYdney that can show me their car with an upgraded turbo ??

Starts to boost at 2100, full boost at 3800 -4000, keeps going until rev limiter of 8000rpm

HKS stuff is awesome for higher boost as well. I can't think of another turbo that will make 230rwkw and still drive like a stocker down low

Chris - The HKS sounds like a damn nice turbo, wanna sell ??

Lowlux - how does the car drive with the VG30 ?? ie when does boost start to kick in, when is it on full boost and when does it start to die off ??

How much of a difference is there to the standard turbo ??

High flowing a stock turbo should include a new stainless steel spindle and intake/exhaust wheels.

You should be looking at well over 20psi safely on a flowed stock.

The translates to much more than the 15-20rwkw you speak of...

This also does not take into account larger trim wheels you can install.

T.

Nah, its not for sale. You should be able to pick one up for around $1500, but they are hard to find. Maybe even look at a HKS 2530,2540,2535. These are a bit bigger and make more power but have more lag

tlai909 - I don't doubt that high flows can make power, but the ones I have seen have hardly made 20rwkw more at higher boost. For what people I know have paid for these they haven't got a good gain for the money spent.

I have seen a couple of rb25 high flows that have made good power though, but its hard to compare them with a rb20 high flow

I think it also comes down to cost.

I got some OUTRAGEOUS figures to flow and refurb a stock turbo (up to $2,500!!!).

In this case a HKS2540 is your friend :rolleyes:

On the plus side a flow stock obviously is easy on install, uses the same pipes and does not alert the police OR insurance :D

T.

I am currently running an rb 25 turbo andhave run a vg 30 turbo on my car the rb 25 turbo doesnt make as much paower as the cg 30 but come in earlier my car has run a 14 flat @ 98 mph the car made 148 rwkw and could of made more as the tune was conservative from the sounds of it the hks turbos are the way to go. I have driven a car with a hi flowed vg 30 turbo it was awsome (dr_drifts old car thecar ran a 108 mph at the drags but had to much wheel spinfor a great time that or the hiflow rb25 turbo is the next option I"m considering at the moment.

as a guide you really dont want the exhaust wheel much larger than 54 mm on

an rb 20 as this makes the car way to laggy ie full boost over 5 k rpm

a cremapped ecu makes a world of difference as well we found gains of 15-20 rwkw at a recent dyno day

meggala

Hi guys, on our RB20DET we have tried;

*standard RB20 turbo (spat the ceramic turbine at 10 psi)

*standard VG30 turbo (in fact 3 of them, 'till we found a reasonable one, but even it spat the dummy shortly after)

*standard RB25 turbo (good for 20 rwkw more than RB20 turbo at the same boost)

*hi flowed RB25 turbo (good for 350 bhp = 210 rwkw at 1.3 bar)

*HKS 2540 (also good for 210 rwkw at 1.5 bar, but way more lag than the RB25 hi flow)

So my recommendation would be hi flowed RB25 turbo, as the other guys have said, it fits straight on, no fabrication required, looks like a standard turbo (has Nissan written on it). When you get a turbo hi flowed you basically end up getting a brand new turbo back as all of the bits that wear are replaced plus the rotating bits are micro balanced. We use GCG turbos for our hi flows as they listen to what the customer wants and then make up a turbo to suite their requirements.

Plus one of our RB25 hi flowed turbo's has just had an upgrade to 55 lbs per minute of airflow at 1.4 bar (should be good for a bit more than 550 bhp), way cheaper than buying another turbo.

Hope that helps.

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