GT2871r or GT3071r for SR20 Redtop???

[firefighter573]

Ok so i have a tough decision here for my Redtop SR, I want somethin that is gonna give me some awesome power and response, but yet i dont want to be boosting 20 psi everywhere i go to make 400whp. My goal is a daily and reliable 400 to the wheels.http://www.houston240sx.com/images/smilies/naughty.gif

Somethin good for the street, but a little bit of a highway monster also.
And im wanting to go topmount.

I've been lookin around at some other forums and i cant really get a solid answer, so I wanna know your .02 if you currently own or have owned a GT2871r or GT3071r.

Im at stock settings currently, stock boost, stock internals, T25, and just a FMIC and BOV and Z32 Fuel Filter

I am doing a complete rebuild with forged internals. I want 100% out of this engine to somewhat be reliable for daily driving. Im also curious to see if i should do a complete rebuild? or keep my bottom end stock and just replace bearings and rings, and build the head..

cheap, fast, and reliable...if i can only have 2 i want fast and reliable.

what setups would ya'll suggest?

oh....and i wanna burn Z06 vettes after this build http://www.houston240sx.com/images/smilies/wink.gif

[TFD]

400whp is pushing it with the help of some nice mods like cams and intake on a 2871 @<20 psi.

Wanting daily / topmount / easy 400? => gt3071 (.63) is your answer then between the two options.

Not from my own experience btw (running a 2871 .86) but, I was in your situation some time ago and SEARCHED a lot for the answer.

Good luck with the build.

[Slidin' Sam]

"cheap, fast, and reliable" - these should never go together.

Why do you want to go topmount? Running a good bottom mount turbo on the street will drop produce a little less hp than your target, but it will be a lot more fun.

When you do your re-build, do everything you can to protect the motor. Ex: just because some jackass say's you don't need RAS, common, their 75 bucks and they wont hurt anything...better safe than sorry.

SEARCH other peoples builds and see what they did and what the results were.

Last note, what transmission do you plan on using, because 400hp is about the breaking point for SR mission.

[240sx123$]

what setups would ya'll suggest?


An LS1 swap.

Youre gonna spend a fortune to get the SR to where an LS is with I/H/E.

[vegasS12]

haha that what my goals were are first just build head and leave block stock but then things change and now im going fully built with. if you can just go with the GT3071r
and upgrade everything you can on the longblock while its torn apart....

[jspaeth]

"cheap, fast, and reliable" - these should never go together.

Why do you want to go topmount? Running a good bottom mount turbo on the street will drop produce a little less hp than your target, but it will be a lot more fun.

When you do your re-build, do everything you can to protect the motor. Ex: just because some jackass say's you don't need RAS, common, their 75 bucks and they wont hurt anything...better safe than sorry.

SEARCH other peoples builds and see what they did and what the results were.

Last note, what transmission do you plan on using, because 400hp is about the breaking point for SR mission.

I know what you are saying, but torque is what kills the transmission.

semantics probably.

[PoorMans180SX]

Get a twin-scroll 3071R with a .63 or .78 turbine housing.

Faster spool than a 2871r, and more power.

Done.

[jspaeth]

Get a twin-scroll 3071R with a .63 or .78 turbine housing.

Faster spool than a 2871r, and more power.

Done.

I have heard from some people that twin-scroll is a good "theory" but doesn't actually do anything in practice.

It sounds legit to me and seems to makes sense as to why it would be better...i dunno

[PoorMans180SX]

I have heard from some people that twin-scroll is a good "theory" but doesn't actually do anything in practice.

It sounds legit to me and seems to makes sense as to why it would be better...i dunno

Go punch those "some people" in the face. It's a well-proven theory. AKA a fact that twin-scroll turbines outspool the same size single scroll ones if tuned correctly.

Why else would OEM's be going to twin-scroll?

[mattsil80wis]

my car makes 403hp on the cody ace setup (too tired to type it all)

ill say this...buy yourself a 700 dollar beater...

if your doing the 71r i would say just do pistons, but if your doing the 30r i would say do rods too....as for building the head, thats on you...cody ace and i run stock heads other than the JWT s3 cams and both make over 400hp

i would also say put gears into it....i run 4.40s and love them

the car runs pretty good on the highway

YouTube - 4-19-10 Junkyard Dog SR20 Sil80 matt vs srt4 vs 636 roll race (http://www.youtube.com/watch?v=dAi9MEiwPtA)

here is a video of it on the highway