3sgte turbo upgrade which to get Options

[mk7celica]

Hello, I am kinda new here. I have a 1994 celica with a 3sgte swap with no engine mods but have a 3 inch dp and full 3 inch exhaust and a fcd, 4 inck air filter with custom air intake pipe and ebay special fmic. What I want to do is upgrade my turbo from the ct26. Dont want a ct27 or rebuild upgrade < figure I will want to upgrade again with these>Can I use any turbo I pick to my liking and bolt to my manifold with a adaptor or get a new manifold as long as I have A external wastegate and the down pipe that bolts to the turbo and exhaust. what I mean is if I have a turbo, wastegate and proper fittment to my manifold it will work? And also Do I have to have a ems to run right with the new turbo,I read that the ecu cuts out at 275 hp is that to the wheels or crank and is it the same for a jdm engine. Also ?i have some bigger injectors on my list to get is this a must with a new turbo?

[mk7celica]

SoDo you think If I get a rebuilt upgrade ct26 similir to the ct27 but bigger. The one I am looking at is a 54 trim garret housing .80A/R exhaust .63A/R to4e and ats rom tune cause I think they can tune a upgraded ct26 550 injectors and fuel rail I can DO 300-325hp? alreadt have walbro pump

[_Jim_]

SoDo you think If I get a rebuilt upgrade ct26 similir to the ct27 but bigger. The one I am looking at is a 54 trim garret housing .80A/R exhaust .63A/R to4e and ats rom tune cause I think they can tune a upgraded ct26 550 injectors and fuel rail I can DO 300-325hp? alreadt have walbro pump

You dont seem to understand how a rom tune works. You have to use a turbo that is VERY similar/identical to the turbo they offer the rom tune for. This is because they tune the ECU to the files that they have on hand. If you buy this "upgraded turbo" from another website and it flows more air then the CT27 you will have a lean condition....and will have to send the ECU back to ATS SEVERAL times before you can starighten out your AFR's. That is assuming that ATS will even sell you a Rom tune for the turbo you were describing.

I may be mistaken.....but last time I called ATS (this was about 2 years ago) they werent going to offer the CT27 with the 550 tune anymore because it just wasnt needed.

A CT27 or a CT20B at 18psi will yield about 280whp on a GEN2.