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Hey guys.

Just wondering if a Garrett GT3071R with .86 exhaust housing will be right for my application?

I have a stock RB20DET in a silvia and was wondering if this turbo would be too big?

Im wanting to run a flat 13/high 12 1/4 mile. put out somewhere around 300rwhp.

Any help much apprechiated.

ALSO, It already has the T25 flange, so it will bolt up to standed rb20 and rb25 manifolds? What else will i need?

Will i NEED any supporting mods just to run this turbo?

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Hey guys.

Just wondering if a Garrett GT3071R with .86 exhaust housing will be right for my application?

I have a stock RB20DET in a silvia and was wondering if this turbo would be too big?

Im wanting to run a flat 13/high 12 1/4 mile. put out somewhere around 300rwhp.

Any help much apprechiated.

ALSO, It already has the T25 flange, so it will bolt up to standed rb20 and rb25 manifolds? What else will i need?

Will i NEED any supporting mods just to run this turbo?

I know that rb25's have a T3 flange, pretty sure rb20's do as well.

Also for 300hp (225rwkw) i think a high flow rb25 turbo would do that for less money and no need for custom dump pipes and intakes that you would need for a 3071R, i do think that the .8 may be a little big for a 20 tho.

Hey guys.

Just wondering if a Garrett GT3071R with .86 exhaust housing will be right for my application?

I have a stock RB20DET in a silvia and was wondering if this turbo would be too big?

Im wanting to run a flat 13/high 12 1/4 mile. put out somewhere around 300rwhp.

Any help much apprechiated.

ALSO, It already has the T25 flange, so it will bolt up to standed rb20 and rb25 manifolds? What else will i need?

Will i NEED any supporting mods just to run this turbo?

Nice choice, however

a high flow T28 (RB25 VG30)might achieve that number heaps quicker !

Argh! T25 are not the same as t3, t25 are same as t2.....

Any sugestions if i wanted to upgrade turbo? i know alot of people use the HKS 2530 or 2535, anything else that might meet my needs? Or if i want to get 300 ponys out of the RB25 turbo what should i be spending the $$ on?

I would suggest a high flow, cheap and pretty much a straight bolt on, other things you will need for 300hp is injectors, fuel pump, afm, management and if you dont already have them 3" exhaust and a fmic.

Edited by W0rp3D
Nice choice, however

a high flow T28 (RB25 VG30)might achieve that number heaps quicker !

Im just not happy with how my current turbo feels coming onto boost, recently nsold my RB25DET VL with a Garrett GT3540 which when boost came on would pin me to my seat. I mean it was laggy as hell but loved the feeling, any good turbos to give me something between the two?

Argh! T25 are not the same as t3, t25 are same as t2.....

Any sugestions if i wanted to upgrade turbo? i know alot of people use the HKS 2530 or 2535, anything else that might meet my needs? Or if i want to get 300 ponys out of the RB25 turbo what should i be spending the $$ on?

I had 360 rwhp with my high flow on a Rb25/30.

Full boost at 2400 rpm.

Just like having a V8 under the hood.

GCG flog em for $1850.

Looks like you're stuck with a T25.

Don't forget you can custom choose what wheels and cartridge you want.

A proper T3 GT3071R with a .63 turbine housing would be much better suited to an RB20.

I still think it's big, I had a 2871R and found it stupidly laggy on my RB20,

Running a RB25 turbo @ 1bar would yield 200rwKws on a RB20 with a good tune, i.e. good timing & mixture

If you want to stay with the std RB20DET exhaust manifold it means using a turbocharger with a "T3" flange . From HKS it could be something like a GT2530 or GT2535 or GTRS which is a 52 compressor trim GT2871R . Just make sure you ask for the RB spec ones because they were also made with T2/25/28 (same) sized mounting flange on their turbine housings for CA18/SR20/RB26 . The RB20/25 specific GTRS also has a port shrouded compressor housing and the 2530 Kai may have it as well . Very important on a small capacity six .

Most people find generic GT2871R's laggy because they usually get or opt for the largest (56T) compressor and IMO it's a bit much for the GT28 turbine to drive . Garrett make the GT2871R in 48/52/56 compressor trims .

The GCG Hi Flow could probably get you there though be aware that the RB25DET's turbine housing looks virtually the same as the RB20's one but it is a little bit larger in its internal passage so starting with an RB25's turbo would be a better bet than an R32 RB20's one . I think the VG30 BB turbos turbine housing would be too big and laggy on an RB20 .

GCG and some other mobs used to sell an aftermarket turbine housing with a T3 mounting flange and was set up to accept a Garrett ball bearing GT cartridge , the buyer option which one and it was profile machined to suit it's turbine . It also had the std RB20/25 dump flange pattern .

It would be possible to fit the cartridge from a GT2860RS or GT2871R into one or possibly use an original RB25 one .

It comes down to your priorities of how much to spend and how easy to fit up .

A real GT3071R is going to be a bit bulky for a 300 Hp turbo and has the biggest chance of being laggy because it's GT30 turbine is designed for a fair bit higher power output - 300 Kw + .

Maybe for starters you could try a std RB25 turbocharger with the RB20's wastegate actuator , just remember it still has the ceramic turbine and in some cases the composite compressor wheel so don't be greedy with boost or they die a quick death .

It won't give you 225 Kw but it should be easy and reasonably cheap , they make ~ 185Kw on an R33 RB25DET .

Options , cheers A .

anyone have any experience with the GT-RS and the GT2535 on a RB20?

i would like to know what kind of power there capable of on the 2litre and when to expect full boost.

thinking of going down the gt2530 as i like the boost curve and its a decent amount of power, but would like over 240rwkw if im going to spend that much.

how would these compare, in terms of power and response. anyone have dyno sheets i can have a look at?

thanks.

anyone have any experience with the GT-RS and the GT2535 on a RB20?

i would like to know what kind of power there capable of on the 2litre and when to expect full boost.

thinking of going down the gt2530 as i like the boost curve and its a decent amount of power, but would like over 240rwkw if im going to spend that much.

how would these compare, in terms of power and response. anyone have dyno sheets i can have a look at?

thanks.

GT-RS is lagger on an RB20 then a TD06-20G setup. I say setup as it included manifold, gate and turbo. So not a fair comparison when up against a bolt on GT-RS...but that gives you an idea. A little less power and a bit more lag from the GT-RS, but bolt on convenience

A while back someone here , Lithium ? , made up a Hi Flow using a Garrett GT2871R (48 comp trim) cartridge in re profiled I think RB25 turbos housings . I think his was in an R33 GTS25T and from memory he said it was very smooth power wise with a bit more everywhere .

Something like this should be more than capable of making 300 hp on an RB20DET and it uses housings intended for an RB engine .

Ask him , cheers A .

GT-RS is lagger on an RB20 then a TD06-20G setup. I say setup as it included manifold, gate and turbo. So not a fair comparison when up against a bolt on GT-RS...but that gives you an idea. A little less power and a bit more lag from the GT-RS, but bolt on convenience

thanks for that mate.

hows the GT2535 go? is it much laggier then the GT2530? is it worth the lag for the better high end.

Thanks alot everyone for all the responses. Have done abit more research and thanks to the help from you guys i have alot more to base my descion on and i am thinking towards the HKS 2535.

Just wondering... Is there a rule of thumb for injector sizes?

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