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Since my web site is no longer on the www I thought I'd share some interesting and exciting news about rb20det tuning. My mates S13 with RB20DET has just recorded 257rwkw on a DDDyno. This is the same dyno that we have always used and the tuner is the same only thing is that this time is was really hot and the final run was done after a full days tune.

Main (Important Mods)

RB20DET (totally stock internals)

T3/T4 hybrid turbo

ARE front mount

Microtech MT12

HKS cam gears

Pump fuel

18psi

4" dump and 3.5" system

Oil catch can

HKS filter

GTR injectors

Bosch 910 fuel pump

OS twin plate

So there is plenty of power available from the ol RB20 so long as you get 1 thing right......Find a good tuner that actually knows what he/she is doing and is more than happy to talk to you, tell you whats happening, lets you spend the day with him to learn whats going on and even lend a hand.

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https://www.sau.com.au/forums/topic/8317-250rwkw-rb20det-how-2/
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Sure, the guys name is Tim and he works for Cramer Dyno & Performance in Toowoomba. The business started out as a Diesel workshop but now most of their business is performance orientated. They supply and install MOTEC, Unichip and so on but the main thing with them is that they are eager to learn and don't charge for time spent "Figuring it out" as they see it as a learning time for them selves.

For those readers of ZOOM you may remember the Yellow 240Z from the cover some time back well that guy lives in Sydney and he had Tim do all the tuning. Their workshop is immaculate and all the staff are well trained.

Their contact details are PH 07 46 989350 if you contact them tell them you spoke to Cam on the Skylines Australia Forum and they will look after you :(

Saying "T3/T4 Turbo" is about as useful as saying "big cams" :thumbsup:

There is no such thing as a standard T3/T4 Turbo, like there is a standard HKS GT2835R. A T3/T4 is a term made up to describe a turbo with a "T3 sized exhaust housing and a T4 sized compressor housing"... It is something the turbocharger specialist/builder such as XTR, GCG (just two examples), etc puts together for the customer's needs.

One T3/T4 will differ from the next one in terms of compressor and exhaust wheel trims, compressor and exhaust A/R ratios, and what kind of bearings are in the center pack.

rb25 will do it so much easier then a rb20

with a full exhaust, piggy back system & 10psi they are doin 160rwkw on a dyno

How did your mate fit the gtr injectors, did he get a resistor pack off a gtr or get a link ecu with the resistor pack?

the ohm that the rb20 produce are to high for the gtr injectors.

T3/T4 is a loose term used, its getting the best of both worlds from the 2 turbo, its a hybrid turbo.

the T4 compressor wheel & the exhaust housing from a T3 to reduce the lag from a very big t04 exhaust housing eg .90

Guest Works Auto
Originally posted by Joe

rb25 will do it so much easier then a rb20

with a full exhaust, piggy back system & 10psi they are doin 160rwkw on a dyno

What a crock of crap. Every rb25 ive seen do more than 300 at the wheels has cracked a ring land or something like that.

There just not suited to high boost . There like a NA motor with a turbo on them.

fair enough, i dont own or know any people with r33 over 250rwkw so i cant say nothing there, but they do tend to ping pretty easy.

Most of the fast r33 that you read on the mag are rb25 head rb30 bottom end.

Why i said the rb25det gets a bigger power figure is because they have 500cc more then we rb20det owners, & can produce 160-170rwkw so easy with just a few mods.

Once you reach above 250rwkw, people tend to break things regradless or rb20 or rb25, engineers never design the engine internals to produce that amount of power.

Im a fan of the whole "RB" engine

Originally posted by Works Auto
Originally posted by Joe

rb25 will do it so much easier then a rb20

with a full exhaust, piggy back system & 10psi they are doin 160rwkw on a dyno

What a crock of crap. Every rb25 ive seen do more than 300 at the wheels has cracked a ring land or something like that.

There just not suited to high boost . There like a NA motor with a turbo on them.

I take it you haven't seen many 300+rwhp RB25DET's then!

I've seen/witnessed/heard of many internally stock RB25DET's that produce a reliable 300+rwhp, mine included. There are a few internally stock RB25DET's in the 400rwhp region that haven't cracked rings or pistons & are still going strong. The red JMS GTS25t is one I've watched run 290-300rwkw quite a few times, & it certainly would cop a hiding!

A 200rwhp RB25DET will crack a ring land if it's poorly tuned, or any of the support systems fail (f/pump etc..)

Both the RB20 & RB25 DET engines have great potential, but you can't overlook the extra 500cc capacity for driveability. It'll bring a bigger turbo on boost sooner, better off-boost response & so on. That's not to say the RB20DET doesn't have advantages over its newer/larger brother. Lower compression being the main one.

While talking CR's it's interesting to note the CR chosen by many of the Japanese tuners (& now a few Aussies) CR's in the region of 9.0:1 & over are not uncommon @ all! It all comes down to the tuning & fuel used.

John (Munro) on these forums has an RB26DETT (OS Giken RB30 kitted) with 9.1:1 CR This CR & extra capacity has his 2835R's spooled & providing solid boost by 4k.

Originally posted by Works Auto

What a crock of crap. Every rb25 ive seen do more than 300 at the wheels has cracked a ring land or something like that.

There just not suited to high boost . There like a NA motor with a turbo on them.

Every single word in this post is complete and utter rubbish.

That's right. EVERY. SINGLE. WORD. :thumbsup:

Merli,I agree with you, I think some people take things to extremes.

Works Auto,

There are issues with all engines, few of them insurmountable, and to say sweeping statements like that leaves you open to the ridicule you will get.

There are a number of RB25 engines producing high horsepower, and while many will go for forged internals that is something most engines will need sooner or later. I know plenty of RB26's that have dropped pistons etc.

To get 250rwkw from an RB20 is a very good effort, testament to the RB family of very tough engines.

See'ya :burnout:

Sorry folks I didn't mean to cause a stir by not supplying the specs. So here you go, I trust this is sufficient for you Merli.

COMPRESSOR SIDE:

Cover - To4B with 3" Inlet 0.6 AR

Wheel - To4B v1 / v2

CENTER:

RX7 Hitachi

TURBINE SIDE:

Housing - Safari FORD pickup 0.64 AR (T3)

Wheel - RX7 HITACHI with Cropped fins

Gate - Internal 4mm oversized

We came up with the specs and components for this several years ago and since then JMS have used a similar design GCG also use a very close design but our Turbine housing is much bigger. Here is a pick of the stock RB20det turbo next to ours.

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