ultimateirving

Got this baby in the mail today. Finally some faster spool.
.64 snail housing

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Z32 with lq4 swap
Desert Street Scene || Dssevents.com

lg54

Hey guys, i have a quick question, please guide me in the right direction. Currently my set up is stock bottom end Sr, Tomei Poncams Type R , Tomei Rocker Arm Stopper and Nismo 555cc Injectors with a HKS 2530. I make 350whp at 1 bar race gas. I am currently looking for 400whp. Will a 2871 get me to 400whp with a forged bottom and top end with the tomei cams? How fast would i reach full boost?

Dboyizmlg

Your in the right direction.

I suggest you read several pages of this thread.

Def

You need more injector to hit 400 rwhp.

A 0.64 A/R 2871R is right on the limit of doing 400 rwhp, sometimes it can do it, othertimes it can't. It also depends on how much boost you're comfortable with running.

As far as RPM to full boost, it's around 4000-4200 RPM on a dyno in 4th.

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S13 Hatch - Goes around tracks quickly
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lg54

Yeah i forgot to add injectors. What is the boost limit efficiency wise in the 2871? Should I go 3071 for reliability? I just want to get the best combination possible 400hp and fastest full boost. All that playing safe boostwise.

Tom N

Get a 20g in a 8cm T2 housing.

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98 240sx w/ S15 SR20DET, T2 20g, 11.22 @ 124.98

Dboyizmlg

Depends on what fuel you tune it with.

91 octane would be 18-20psi max.
E85 can do 22-23psi

I would tune it with E85, every one has their own opinion.
You can reach the 400whp mark several ways with different turbos and fuels.
GTX2867r offers awesome spool time, and great powerband better than the Gt2871r.

EFR turbos are good too

There are soo many things I suggest you do a bit of research.

S14DB

On a Delorean?

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Comments should be taken as Opinions not as Statements of Fact

Tom N

Sure?


............

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98 240sx w/ S15 SR20DET, T2 20g, 11.22 @ 124.98

Kingtal0n

The secret of time travel has been evoked! dat 8cm t2 flux-housing

Had a pair of 17c turbos from a GM cyclone installed on a 355cid engine once

I Still feel that the ultimate combo for a stock bottom end sr is the 64 2871r on the oem manifolds with S3 cams and thats it, no springs or rocker stoppers or any funny business aftermarket regulators shiny lines or gadgets none of that. KISS

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Tom N

450hp at 24psi and full boost by 4k rpms works for me. I'll take a 20g over a 2871 and day.

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98 240sx w/ S15 SR20DET, T2 20g, 11.22 @ 124.98

gotta240

Maybe post in the 20g turbo thread then?

Tom N

Someone asked about something good for a fast spooling 400hp turbo. I recommended a 20g. So how about relaxing a bit. It's the Internet.

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98 240sx w/ S15 SR20DET, T2 20g, 11.22 @ 124.98

Dboyizmlg

What fuel was it tuned with?

Tom N

Pump gas and meth injection.

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98 240sx w/ S15 SR20DET, T2 20g, 11.22 @ 124.98

Dboyizmlg

I wonder if any one has tried extrude honed intake manifold in addition with the exhaust mani, and 2871r.

I've been really thinking about extrude honing the I/M with my set up.
It would be interesting to see what tq and peak power gains would be compared to a greddy/Freddy I/M.

Tom N

I have a extrude honed intake and my power band pulls to 8k rpms.

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98 240sx w/ S15 SR20DET, T2 20g, 11.22 @ 124.98

Dboyizmlg

NEW GTX2871R!

Garret just made a new 2871r, some one on here posted a thread at Sema show.

Any one have details???

Dboyizmlg

Link to thread for GTX2871r

http://zilvia.net/f/showthread.php?t=582922

lg54

aww mann. I just got more confused after reading a couple pages. Would the GT2871 make 400hp reliably? I just dont want the lag of the 3071. Maybe ill have to take down my power goals 380-390. GTX2867r vs GT2871? or the new GTX2871? so confusing

Dirtcanhurt089

Yeah garrett released the new gtx2971 trying to upload a pic of it from sema

slideslidegnarslide

i just have a few questions, more or less to ease my mind. I am currently installing tomei poncams, tomei head gaskets,740cc injectors and arp studs. (also did tomei oil pan new pick up oil pump and water pump but thats just for good measure, no real performance there) My question is what is a safe boost level for the stock bottom end? Most of the time i see every one between 16-20 psi. I was thinking of shooting for 18. I am not as concerned about the numbers i make more concerned with the way the car drives and that I am not going to be on the ragged edge of what the stock bottom end can hold. So for the guys that have been running these for a while, is 18 psi too much for a nice reliable turn key car? Last thing i want after putting this car together is for it to let go on the dyno. I have bounced the idea off of some friends heads and have done my own research and I think 18 psi is safe. Any input?

idk why i am having these fears. I know people run these engines with this turbo at that boost level but how long are they lasting?

kaoliu

When I got my Sr tuned at Church Automotive in Wilmington, ca, I told the guy that I wanted a conservative tune on the safe side. With that said, I ended up at18 psi for the highest setting and netted 328hp 306tq on a dynapack. So my guess is that you'll be fine, since that's what Church Automotive tuned me at.

My build consisted of:
Garrett gt2871r. 64
740cc Tomei injectors
New OEM headgaskket
ARP headstone
Automotive FPR
power FC D-Jetro
Isis front mount intercooler kit

slideslidegnarslide

How long has the car been running 18 psi? I do not have an electronic boost controller. Maybe I should invest in one

kaoliu

This was 3 months ago, and I drive it at 12 psi normally. When I set it at 18psi, my a/f and knock readings indicates that there's nothing to worry about. But that's my build.

Since you have a metal headgasket, your engine has the parts to hold fine pass 18psi - assuming your block and head mating surface was within. 001 inch or resurfaced, and more importantly, tuned.

As for the electronic boost controller, it's convenient to be able to change boost levels within the car. But it's just that, convenience. If you don't mind popping your hood to change boost levels, then you don't need it.

And you mentioned that you don't care about numbers as long as it's safe. Well, 7-12 is what the stock block runs anyway. Why not just stick with that?

slideslidegnarslide

Well obviously I am looking to make a considerable power leap but I'm not chasing a magic number. I had the car on 10 lbs and found it rather boring. That is why I am doing the cams and supporting mods to turn the boost up. Just looking for a happy medium between good power and reliability. The head and block are with in tolerance and it will be running a power fc as engine management. Tune will be done by a reputable shop (rt tuning). Thank you for your response man. Giving me some piece of mind.

Purestock240

where do most peoples setups hit full boost? and what would it be on a stock t25?

kaoliu

Take it for what it is, I think you should be fine/happy at 18psi. Metal headgasket, checked. Good turbo, checked. Injectors, checked. Management, checked. Head studs, checked. Feeling happy after everything, pending.

If you are dead set on who is tuning your car, then talk to them to get their opinion. They will know better than someone on the forum, like me, on what works. That's probably my best advice. Talk to your tuner and express your concerns.

Dboyizmlg

Tom is this s14 SR intake manifold?

Tom N

If you're asking me if that is what I have the answer is no.
I have a stock S14 intake manifold that has been extrude honed.

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98 240sx w/ S15 SR20DET, T2 20g, 11.22 @ 124.98