SR20 GT2871R Install

[BR1JZL]

Hi all,

So alot has happened since the timing was redone, etc, long story short motor is out atm and there is shaft play on the turbo and wanting to replace with the GT2871R (not interested in the GT30 series as a DD)

Since I'm based in Aus, we have access to heaps of the GT2871R, but they are generally used for an SR20. I am wanting to know, is .64 A/R fine for our car (stock internals etc) and is there anything else required, such as different dump pipe flange, exhaust manifold etc, as this will not be an ATP kit.

Thanks in advance

[BR1JZL]

or has anyone used the GT2871RS (https://gcg.com.au/Turbo-Charger-Gar...5020S.html)???

Curious to know what sort of figures can be had with this and if it is a straight bolt up

[Spectrix]

The MZR engine uses a different exhaust housing to any of the Garret range. Your options are to use an ATP exhaust housing or a custom made manifold.

[BR1JZL]

Thanks @Spectrix;

since the standard manifold flows well, has anyone used an adaptor plate or welded on a flange? Also will the downpipe bolt up without any issues?

[Spectrix]

Originally Posted by BR1JZL Thanks @Spectrix; since the standard manifold flows well, has anyone used an adaptor plate or welded on a flange? Also will the downpipe bolt up without any issues?

As the Garrett exhaust housing is a different design, the outlet flange wont mate to the MZR dump pipe either.
It's most inconvenient for those of us who have SR20 parts sitting around that would otherwise be a great swap

[Jeff23spl]

what you will save on the sr20 housing will vanish by the extra cost to make it fit...Using an adaptor with reduce the turbo height and probably interfer with everything else needing a completely custom turbo manifold and downpipe...
You may check what is the ATP GT28 housing AR to compare but i think it the RS would be a smaller trim and possibly smaller inlet size compared to the ATP GT2871 i have used. I know that one is making a very good spooling turbo for conservative power.
And you could go well further with let say, new wheel design and bolt on flanges....Like an ATP GTX2867 that out flow the old 2871 with a better spool for dayly driving....There is also cheaper options like BNR and Corksport with oem flanges without ball bearings...

[BR1JZL]

ah man, what a PITA, I was thinking an exhaust shop could cut the old flange off and weld on a T04 flange because the GT2871R and GTX2867R are under 1k here (some are $500 2nd hand) and the BNR Stage 3 and Corksport turbos are around 1.8k. Well looks like I will be sticking with an eBay K04 replacement ($150), until I can save up again.

Thanks guys

[Jeff23spl]

Not a pita, It is what it is, almost anyone going BT on a low budget would have tough about this and figured out it won't work(Myself included)....You can get an ATP flange for the gt28 and swap the hot side of the sourced low cost turbo....atp sell the external wastegate model or you can try to get the internal wg model by asking them or looking for a blown mazdaspeed turbo and make 1 with 2...

Factory manifold and flanges are usually cast iron so you can't really weld on it and if you do, it will crack....

As a side note, take a look at different Garret model to understand what it is versus copy....There is a good evolution from GT, GTX and GTX gen2 or even the new G550/660......because i don't think you can get a genuine gtx ball bearing model at a lower price than a BNR or Corksport new. Some copy could work but most of them won't last much....Of course you can get something using Garrett numbers on ebay for less than 1k but it won't be a genuine one and for sure, they won't have a Mazdaspeed flange available...

[BR1JZL]

Thanks @Jeff23spl; I might suck it up for a little longer and continue to ride the bus, hahaha. I should mention that I am also running stock internals, and have no plan on using e85. I came across another Garret turbo though, which will bolt up to stock manifold and DP, and not as big as the 3071R, i'm looking at the GTX2971R or the GTX2976R, Mamba are offering these, and seem to fit pretty well

[Jeff23spl]

I'm not tuned yet with a 3076 but i miss my 2871 quick spool on the street and my bottom is forged on meth...
if you don't plan to build the bottom, you don't need a 76mm...a gtx2971 will already outflow what your oem engine and injection can handle....