Thread: GTIR Turbo Manifolds

So a gt3071r is a no go I guess.....




Is this turbo jgy sells? Because I was looking at getting a plain old gt2871r with a .64a/r, so I can have a sick azz mid range and a nice topend to boot!
Also what is the highest boost i should run on a stock block GTi-r with the 71r on the stock gtir manifold?

Get the GT2871R with the .86 AR turbine housing.

Buy the Turbo from anywhere else but the place you listed.

ATP Turbos come to mind.

100000000000 PSI.

I was told the .86 would be laggy and not good for street use and that the 64 would give me a better streetable powrband? what do you think? I want something that is going to kick in low and fast and contrinue until 7800.

A .86 will not be laggy. I only run .86 AR T25 turbos

A GT28RS or GT2871R will not make peak HP up to 7800 RPMs.

These turbos make peak HP on a SR20DE in the 7000-7200 range.

Needing to pull to 7800 RPMs does not make a car fast.

Look a GT2871R will make 400-420 WHP with no problem, run low 11 sec time slips and will pull your car to redline in 5th gears which is 174 MPH with no problem.

Thats all you need to know.

heres the graph :



there were no issues with boost creep on this set up, although they do seem to suffer if running lower boost levels, that can be pretty easily resolved as andreas says by porting the wastegate and using a better dump pipe. Irrc this one was at 1.8 maybe 1.9bar. It was still on the stock elbow and a ****ty 2.5 inch exhaust, you could see the power drop off when the wideband was thrown up the back of it...lol

i fully agree with andreas about using the bigger housing, the smaller housing can cause some part throttle surge issues, there really is no noticable difference with drivabillity on the road either by using the bigger housing.

I dont agree however with going with a 2871, i pretty much hate that turbo. Never seen it do anything worth shouting about, maybe its just us over here Simon ran one on his car a few years ago and tbh the 3071 completely owned it.

I know its all been said before but a 2871 will not make anywhere near 420whp on any dyno in england, you'd be very lucky to get that at the fly.

my choice would be a 3071 everytime on a 2litre gtir, but then again, you dont have the benefit of awd which may cause some traction issues

Well the average

GT28Rs makes 360-370WHP at 17-18 PSI Again these cars run 122-123 MPH in the 1/4 mile

GT2871 makes 400-420 WHP at 20-21 PSI Again these cars run 125-126 MPH in the 1/4 mile

We can talk all the dyno figures are of or high here in the USA but Those MPH speak for themselves on the 1/4 mile, so you guys can call it as you like.

I like the 3071 also but will take the Incon GTBB37 over it.


This is the standard 3071 turbo

700177-0003 GT3071R 56.5 mm 52.0 mm 84 71.0 mm 53.1 mm 56
700177-0004 GT3071R 56.5 mm 54.0 mm 90 71.0 mm 53.1 mm 56

This the turbo know as the GTBB37 incon Turbo. Incon is an Australian company that were the first to make a true divored or divided wastegate housing for the T25. This turbo was able to control boost creep with an internal wastegate because of this feature.

700177-0011 GT3076R 56.5 mm 54.0 mm 90 76.2 mm 55.0 mm 52

This GTBB37 will out muscle anything and will outpower the the 3071R

not calling anything, just saying what we see here

a car with a 2871 wouldn't run close to those times here either For example a gtir running a 2871 would be lucky to run late 11's more likely low 12's. A fwd car wont get anywhere near either tbh.

Maybe its poor track prep or the fact that no one really runs slicks here

possibly cuz on my t25 on 12psi on slicks i pulled 12.4@110mph The b13 at the time weight in at 2200 without me in it. I weigh 180 lbs So i mean not super light but light. When all said and done with the new setup i should be in the 2000 lb even range without me in it.

What is the elevation in England where your at. Never really looked it up. That could be playing a huge factor as well.

Put it this way a buddy that lives in Albequerque New Mexico elevation 5500 ft above sea level in his t28 240 on 14psi could only muster a 14.5@97mph The motor was running on an S13 ecu and was running very well, motors compression was perfect across the board but where he lived thats all he could do. Then he comes over here with it which we are right at sea level and the thing runs hella strong. Hes taking out mid 13 second cars like its nothing.

Then look up the correction factor for 5500 ft above sea level and its a .9 second correction factor with 5-6mph correction in as well. So i would say thats his reason for the bad times. But again he said everyone around him was running slow times as well. Not just him.

I think we have way better tracks here, run slicks, and those gtirs gotta be alot heavier then my stripped b13? Who knows, but whatever the case the 3071r's powerband is not for me. I think I'll stick with the 2871r.

Where can this turbo be bought and how much? Link please?