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rauschmichaeleric

2871R twinscroll?

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Hi @ll!!

 

Little question anyone ever heard about a GT2871R BB twinscroll? is it possible or would it do any good??

I am asking because I am hesitating with the GT3071R BB twinscroll from full race

 

I wonder if the 2 are comparable? would a 3071BB TS spool nearly as fast as a normal GT2871r ?

I aim a quick spooling build engine:

 

( wiseco or tomei skyline- better cooling)- rods,crank pistons maybe 2.2 ,

 

streetable around 350-400 hp with ITB

 

and I am dreaming of a neo vvl worked head ....,

 

haltech ecu E11v2 or would a E8 suffice?

 

nismo gearbox ( wondering if it will hold the torque , factory it sez 392NM , I guess that I will easely exeed it with these mods ( do you know if the std gearbox is T5 or T56 from borg warner? I found a site www.ttcautomotive.com. with nice gearboxes ;

 

big brake kit ,

 

KW variante 3 suspension,

 

small cage,

 

and all the other reinforcement stuff.

 

what do you think guys??or should I wait the new nissan MR20VHRT engine , and just swap en prep a little.

 

 

thanks

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you dont be doing 400hp at the wheels with a gt28, twin scroll or not

300 yeah but 400 is 3076 territory

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similar scroll apparently between 3071r on twin scroll and normal gt2871r.

honestly dont see the point of a gt2871r twin scroll, and would take a custom manifold as they are a t2 flange, not t3 like gt3071r.

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your better off using the Tial housing the juggernaut was going to use on his 2871. The 2871 is a turbine restricted turbo and the Tial housing helps the rear breath better to reach the full potential of the turbo.

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This was going to be my 2871R project (custom 6boost manifold and Tial ex housing):

 

Turbo008.jpg

 

...and then I went for this full-race 3071 twin scroll setup which is currently in progress:

 

full-racemani2.jpg

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Ca bleubird: how do you mean mismatched , what does not match according to you?

what would you do ?

 

would the 3071 bb ts spool as fast? as gt2871

 

btw 2871r 86 is rated 400hp

 

flywheel hp is ok for me

 

thx

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real men measure at the rear wheels

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Ca bleubird: how do you mean mismatched , what does not match according to you?

what would you do ?

 

would the 3071 bb ts spool as fast? as gt2871

 

btw 2871r 86 is rated 400hp

 

flywheel hp is ok for me

 

thx

Garrett Rate the GT2871R 52T to 460HP and the 56T to 475hp but that's based off the compressor maps.

 

52T

http://www.turbobygarrett.com/turbobygarre...R_472560_15.htm

 

56T

http://www.turbobygarrett.com/turbobygarre...1R_743347_2.htm

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Ca bleubird: how do you mean mismatched , what does not match according to you?

what would you do ?

 

would the 3071 bb ts spool as fast? as gt2871

 

btw 2871r 86 is rated 400hp

 

flywheel hp is ok for me

 

thx

 

ok the reason it is missmatched is because that particular turbo runs a relatively big compressor with a relatively small turbine, which is a good match for your run of the mill sr20det as it gives response. But if your dreaming of going vet, then things change a little, the ve head is very high flowing and the cams have a lot of overlap, i think that a gt2871r running high boost could possibly cause reversion.

 

It is also a bad match as you are looking at a twin scroll set up on such a small rear wheel, there is no point imo, the turbine is so small i doubt it would benefit much or at all from a twin scroll. There might be some small benefits if set up 100% but a twin scroll is much harder to get 100% over conventional, and the $$$ spend on manifold design, housing etc would not nearly be worth it due to the sheer size of the turbine.

 

if you are serious about going ve i would either go the twin scroll 3071r out of the two with well designed tubular manifold and ve cams, or the 2871 with either the tial housing or standard .64 and vet cams.

 

Also the 2871r is probably not the best turbo for a 2.2l even with a worked det head

 

ontop of this the gt2871r wont flow 400rwhp, well not on a dyno dynamics dyno anyway

 

these are the reasons i think its missmatched

 

When turbo shopping my ve i decided to go with a rear wheel similar to the gt3071 and a 76mm comp wheel but with a reasonably small 54mm inducer to help with lag

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Ca bleubird: how do you mean mismatched , what does not match according to you?

what would you do ?

 

would the 3071 bb ts spool as fast? as gt2871

 

btw 2871r 86 is rated 400hp

 

flywheel hp is ok for me

 

thx

 

ok the reason it is missmatched is because that particular turbo runs a relatively big compressor with a relatively small turbine, which is a good match for your run of the mill sr20det as it gives response. But if your dreaming of going vet, then things change a little, the ve head is very high flowing and the cams have a lot of overlap, i think that a gt2871r running high boost could possibly cause reversion.

 

It is also a bad match as you are looking at a twin scroll set up on such a small rear wheel, there is no point imo, the turbine is so small i doubt it would benefit much or at all from a twin scroll. There might be some small benefits if set up 100% but a twin scroll is much harder to get 100% over conventional, and the $$$ spend on manifold design, housing etc would not nearly be worth it due to the sheer size of the turbine.

 

if you are serious about going ve i would either go the twin scroll 3071r out of the two with well designed tubular manifold and ve cams, or the 2871 with either the tial housing or standard .64 and vet cams.

 

Also the 2871r is probably not the best turbo for a 2.2l even with a worked det head

 

ontop of this the gt2871r wont flow 400rwhp, well not on a dyno dynamics dyno anyway

 

these are the reasons i think its missmatched

 

When turbo shopping my ve i decided to go with a rear wheel similar to the gt3071 and a 76mm comp wheel but with a reasonably small 54mm inducer to help with lag

 

ok thx alot for the insight!!!

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If you read some of the comments on the freshalloy forum members are claiming a twin scroll 3071R spools as fast as a 2871R when they've made the switch.

 

If you're think of going 2.2 or bigger, Geoff Raicer (from Full-Race) would not recommend using a twin scroll 3071/76R as he feels this may cause backpressure issues on well worked SR. That's why he has now designed a T4 manifold and T4 ex housing and mated that to a GT35.

 

On a Subaru WRX with an EJ25 motor (2.5 litre) this twin scroll T4 GT35 with a 1.06 rear housing made 442 ftlb of torque at the rear wheels at 4133 rpm and 496 rwhp at 6569 rpm. How well would this setup go on a well built SR? When asked the question, Geoff indicated that it would be virtually useless on a rear wheel drive car due to traction issues.

 

Incidently the figures quoted above are from a dynopack dyno.

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If you read some of the comments on the freshalloy forum members are claiming a twin scroll 3071R spools as fast as a 2871R when they've made the switch.

 

If you're think of going 2.2 or bigger, Geoff Raicer (from Full-Race) would not recommend using a twin scroll 3071/76R as he feels this may cause backpressure issues on well worked SR. That's why he has now designed a T4 manifold and T4 ex housing and mated that to a GT35.

 

On a Subaru WRX with an EJ25 motor (2.5 litre) this twin scroll T4 GT35 with a 1.06 rear housing made 442 ftlb of torque at the rear wheels at 4133 rpm and 496 rwhp at 6569 rpm. How well would this setup go on a well built SR? When asked the question, Geoff indicated that it would be virtually useless on a rear wheel drive car due to traction issues.

 

Incidently the figures quoted above are from a dynopack dyno.

 

 

Maybe I should ask myself ( read you guys:-) ) what are the benefit of installing a sr20 20V head ? of course I d like to have as it would be a realy special build , but I am not made out of money and I would only do it if there are some benefits to it ,

 

who can answer me this, but I mean realy specific .

 

same for the ITB which would bring me to the next question I think I know the Ikeya formula ITB go on a DET head , but would they fit on the 20V head to? or would I be looking at a custom ITB build.

 

As on cc I would not go bigger as 86.5 x 91 which should be +/- 2.1L

 

GT35 would be to big for me

I am trying to find the middle between a highway monster and a something spooling as fast a I drop the panties of my girlfriend :-)!

That why I am hesitating between a good 2871r a/r .86 or the 3071 TS and ofcourse I love the TS manifold it is a piece of art .

 

So what CC would you guys advice?

What boost level?and what max boost level (think reliablility not powerlevels )

What torque should I expect according to you guys ?

what gearbox would you guys use? I thought I would be going for the nismo 6 speed ( 392 NM) but now I am doubting , affraid that the torque output will be higher.

 

 

thanx again for your input

 

I guess the purpose of my build is to have a reliable but special build, and to have lots of when when driving it!

Edited by rauschmichaeleric

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Ca bleubird: how do you mean mismatched , what does not match according to you?

what would you do ?

 

would the 3071 bb ts spool as fast? as gt2871

 

btw 2871r 86 is rated 400hp

 

flywheel hp is ok for me

 

thx

 

ok the reason it is missmatched is because that particular turbo runs a relatively big compressor with a relatively small turbine, which is a good match for your run of the mill sr20det as it gives response. But if your dreaming of going vet, then things change a little, the ve head is very high flowing and the cams have a lot of overlap, i think that a gt2871r running high boost could possibly cause reversion.

 

It is also a bad match as you are looking at a twin scroll set up on such a small rear wheel, there is no point imo, the turbine is so small i doubt it would benefit much or at all from a twin scroll. There might be some small benefits if set up 100% but a twin scroll is much harder to get 100% over conventional, and the $$$ spend on manifold design, housing etc would not nearly be worth it due to the sheer size of the turbine.

 

if you are serious about going ve i would either go the twin scroll 3071r out of the two with well designed tubular manifold and ve cams, or the 2871 with either the tial housing or standard .64 and vet cams.

 

Also the 2871r is probably not the best turbo for a 2.2l even with a worked det head

 

ontop of this the gt2871r wont flow 400rwhp, well not on a dyno dynamics dyno anyway

 

these are the reasons i think its missmatched

 

When turbo shopping my ve i decided to go with a rear wheel similar to the gt3071 and a 76mm comp wheel but with a reasonably small 54mm inducer to help with lag

 

ok thx alot for the insight!!!

 

 

CA18 blubird,

 

Could you give me a detail of your build please?

Do you also have dyno maps of you car?

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yes you can get itb's for the ve, pm me for the recommendation, the ones i have in mind are quite well prices as they are made by an engineer in a reasonably poor country, but the stuff looks quite sound imo

 

the benefits of itb would be throttle response, and flow, so you can get the benefits of a larger plenum with out the associated throttle lag.

 

i would choose a 3071r twin scroll over the 2871 .86. but if you cant afford a manifold like pictured above i wouldn't buy a twin scrool. just a ,63 gt3071r. There are some other cool options turbowise as well.

 

details of my build....hmm how much should i tell....well i will say this, my build is not 100% finished as of yet, but is not very far off. if you want more detail shoot me a pm

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