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Gday,

I know this has been covered before and I have searched various posts so I have a fair idea but I want to join the 300rwkw club with a street tune of > 280rwkw.

I currently have an R33 GTS-t S1 with an RB25DET. Mods include:

batmbl split dump/front pipe, high flow 5" cat with 3"center, kakimoto 3"cat-back

Apexi Pod Filter

Hybrid GT spec intercooler

PowerFC with EBC add on

Cold Air Intake to help

So far the car has made a max of 250hp at 12psi. I will be purchasing the following items:

Z32 AFM

555cc Nismo injectors

Walbro fuel pump ESS342

My question lies with which turbo and clutch should I go with? I think I'll keep the factory manifold so that I can make use of the batmbl dump/front pipe. I want it to be suited more for circuit track racing.

Ive searched the RB25 dyno results page and these are the options I found:

GT-RS

Gt3540

T04R

Which will best suit my needs and thanks for everyone who puts input in, I just want best for my car! - Cheers

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2835 would go close.

from your original choices: Gtrs too small, 3540 too big, to4r too big.

Garrett based turbos would see the 3071 go close (same basic turbo as the 2835 but un cropped gt30 exhaust wheel) or the 3076 do it easily with a bit of lag.

2835 wouldn't be able to use a 1 peice dump to suit the stock turbo, neither would and internal gated garrett.

A Garrett GT30 based turbo will get you over the line.

There are loads of threads/posts from discopotato03 on all the variants, characteristics and associated information.

Having a good search of his past posts/threads will give you all the info you will need :rofl:

I wouldnt purchase that walbro, get a decent Bosch pump.

While I respect your opion Nismoid, why not go for the Walbro - from what i know they have a 255L/h flow (above 300rwkw) at 45psi. I herd that whilst it requires a small bracket, strainer and wiring modifications it will run straight off the factory fuel line???

What about using the Garrett 3076 with a hks cast low mount manifold that has been extrude honed (thanks tridentt150v) ?? Should I stick with an internal wastegate or move to an external one?

Again cheers for all the info!

I recently went with a GT3076R, although a touch laggier than I expected (150-200 or so rpm) I can definitely say that I am happy with the mid range indeed. You will find you will need a clutch not soon but fairly shortly after buying your turbo as I am coming up to, not to mention the drivers side window motor, gearbox nicking from 3rd to 4th and a kick in the head needs attending to also.

While I respect your opion Nismoid, why not go for the Walbro - from what i know they have a 255L/h flow (above 300rwkw) at 45psi.

Because i had that exact model and it was totally maxed @ 270rwkw/17psi. AFR's were in the 14 range.

Soon as we dropped a bosch in, AFR's went to the 10's instantly. The pump was correctly wired etc etc.

There are many other people who have had walbros and have encountered similar issues that which i have had, so mine wasnt just a once off unfortunately. Seems they can very much be hit and miss

I recently went with a GT3076R, although a touch laggier than I expected (150-200 or so rpm) I can definitely say that I am happy with the mid range indeed. You will find you will need a clutch not soon but fairly shortly after buying your turbo as I am coming up to, not to mention the drivers side window motor, gearbox nicking from 3rd to 4th and a kick in the head needs attending to also.

when did it hit full boost by? how much power did you make?

What about using the Garrett 3076 with a hks cast low mount manifold that has been extrude honed (thanks tridentt150v) ?? Should I stick with an internal wastegate or move to an external one?

I didn't say to do this set up in my PM, I was just saying what I have done. You will have to work out what you want to do and how to achieve it for yourself. My idea's on how to set up a motor may well be radically different to other peoples thoughts.

While I respect your opion Nismoid, why not go for the Walbro - from what i know they have a 255L/h flow (above 300rwkw) at 45psi. I herd that whilst it requires a small bracket, strainer and wiring modifications it will run straight off the factory fuel line???

If you repsct his opinion then why dont you listen to him?

you will find that when running 550 injectors and a FPR you will need say 42psi base fuel pressure.

then crank 20psi of boost into it to get you to 300 kws and the fuel pressure is now at 62 psi.

this is when the walbro dies in the ass.

if you like your engine lasting once you get up to 270 kws and beyond then sell the walbro and get a 044 and mount it in tank in the same spot as th walbro. still runs on standard fuel lines.

its a no brainer....

I also went the GT30/40 it is quite drivable round town, but when you put the hammer down you better hang on...

Also spend some money on tyres, either buy loads of cheap ones, or get some DOT apporved semi slicks as 270+rwkw becomes tail happy... :rofl:

If you repsct his opinion then why dont you listen to him?

you will find that when running 550 injectors and a FPR you will need say 42psi base fuel pressure.

then crank 20psi of boost into it to get you to 300 kws and the fuel pressure is now at 62 psi.

this is when the walbro dies in the ass.

if you like your engine lasting once you get up to 270 kws and beyond then sell the walbro and get a 044 and mount it in tank in the same spot as th walbro. still runs on standard fuel lines.

its a no brainer....

Or a tomei/nismo etc and direct + wire with relay etc.

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