Gt28rs requirements

MspMarcus

Member
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MazdaSPEED Protege, Titanium
Just curious the requirements that follows installing the gt28rs
-injectors
-tuning
anything i'm missing please inform :)
 
i have one on a stock motor and a flashed ECU. its set at 7 psi. no problems of any sort yet (daily driven for about 3 months now). a tune would be really helpful though but i dont have the cash for a piggyback :(

edit: i also have a SRI and FMIC
 
on a gt28rs, even with a tune and FMIC youre pushing danger zone. i would strongly discourage it without a tune.
 
haha i just needed some verification
i actually work at a shop, just the mechanics i work with dont know mazda's and such but they were telling me injectors and fuel pump may possibly be the start, but considering its already turbo'ed stock, the fuel pump might not need to be ungraded.
So all in all just needed everyone elses opinion who might actually have it done.

But im probably doing the Fmic custom job in a month or so, considering the amount of money you can save without through corksport or something.

and i'll throw on a Vibrant exhaust after the fmic, i get them for $700 through my shop ;)
 
then what do u do when your stocker goes crap lol. i wouldnt want to buy another t25 then have to upgrade.
 
if your looking for an exhaust go with the new 80mm corksport only $500.ill be installing mine this weekend
 
if your looking for an exhaust go with the new 80mm corksport only $500.ill be installing mine this weekend

+$200 for the high flow cat.

I for some reason have always been turned off by corksport products, i haven't used any personally but for some reason have no particular desire to buy them
 
I would just get a gt28 and run it at stock boost levels, and not mess with boost UNTILL you have the motor built. IMHO, you can also run a gt30 at stock boost ok.
 
There is almost no lag with the 28RS, once you step up to a T3 it's noticeable but not with the 28.
 
We don't have nearly enough msps on a t3 turbo. Just don't go to lean and you'll see how much the t2 is restricting flow.
 
its actually about the same as a GT28, its only slightly bigger with the compressed housing. And the top end would be better :D


And the GT3071R is on a GT2 flange. It rocks IMHO

oh really? i thought that at stock boost it would lag alot. hmm well i guess i need a gt28 then cause i was like uhhh i dont wanna blow at only 8 psi.
 
I see no lag what so ever either.
The nice thing about the MSP ECU is that it's tuned so damn rich that it could use the larger turbo to lean it out a bit. I honestly think Mazda or should I say racing beat tuned it with the GT28RS on and realized they left very little buffer in terms of zoom-zzom-boom and down graded the turbo but left the tune.
As far as what do you NEED:
I was bone stock when my turbo blew and we replaced just the turbo with a GT28RS and forge WGA set REALLY low.
It ran great that way until my Catless mid-pipe came in and I was able to install the MAM FMIC. So about a month or 2 in the summer. The under hood temps where high, and you could tell the turbo was choking do to the completly stock exhaust. Just the Catless mid-pipe made a world of diffrence, I was making more power, the under hood temps went down, and the turbo was no longer choking.
Then the FMIC went in with a relocated MAF and again she responded fantastic.
Once I finally added a full 3" Perrin exhaust the car finally felt like she was able to stretch her legs completely.
All this was on a stock MSP ECU for about a year.
I finally added a split second just before our dyno day, more for safety then anything.
 
i'm running a ssafc w/supermap ... wouldn't really call that a tune pushing 8psi spikes to 10psi sometimes on a lot bigger turbo. no issues here... running stock injectors, JDM cams (which used to say on PG that it wasn't recommended), 2 3/4 inch exhaust, and a front mount intercooler... really wouldn't say i have all the supporting mods (not forged)... and my car has been running strong for over two years... Daily Driven and Driven Hard... as for lag i have no idea what and how that feels like... all i know at 3500 rpms cruising up a hill in 4th... if i floor it.. i get full boost in like 1-2sec
 
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