Where is my modding going wrong?

Culti

New member
Hey (1st POST!), I've got a 2007 STi.

Here's the current list: AMR C70 turbo, catted DP, amr 2" uel headers, race catback, 38mm ewg, manual boost controller, turbo xs short ram, deatschwerk 850cc injectors, process west top mount, and 255lph fuel pump. The car makes 340whp and 325wtq on 19 psi....

Here's the past... First tune mods: fuel pump, headers, ewg, downpipe, catback, and manual boost controller. 315whp, 365wtq on 19psi. Second Tune: All the above, but swapped to a turbo xs fmic. 325whp, and 345wtq on 19 psi. Third tune, everything's the same but i added the injectors, intake, and turbo. 23psi 354whp and 365wtq. Now im moving backwards....

First of all, im very unhappy because i told my tuner I wanted a turbo capable of 400whp with no meth injection and they told me the amr. I was naive and didnt do research and now i have a $2000 turbo that's worse than the stock. 2nd, I feel like the car should be making way more torque considering I have higher flowing of everything than my 1st tune with just the exhaust. Is the short ram causing torque to drop? I'm still waiting for my process west splitter to come in (UPS fail). I didn't know if any tuners out there know about this turbo and these mods and what the car should be at. I wish I kept the fmic but I've seen people with top mounts make the power I really want to hit. I'm also considering the Blouch 2.5 or the 3.0 Doms as a new turbo option since the AMR is S***. The car also hesitates a lot especially at 2300 rpm 1st through 3rd when you're trying to get on the gas. When i blip the throttle sometimes it sounds like a bubbly noise underwater if you can imagine that. The car is running even richer than before, not sure if that hurts performance. Idle is almost 15 and WOT is 11.5. I'd really like to get some input because I want some justification for a retune. Thanks.
 

IGOTASTi

System Operator
Staff member
Who tuned it?
 

HolyCrapItsFast

Drinks beer!
I see a bunch of things wrong with your setup and your tuner should have sat down with you to discuss them all. The biggest issue is the turbo... or more likely the turbo/header combination. They are very poorly matched. The header tubes are way too big and don't allow sufficient velocity for the turbo to spool quickly. Though the turbo has a 52lbs compressor wheel, it is coupled to a 7cm TD05 turbine wheel which makes it even harder to spool. Plus the small turbine and compressor housing do not make for a high flowing turbo... so Fail all around IMO. What the FUCK were they thinking there? One can only guess. :lol:

Your goal for a Dom 2.5 or 3.0 is right on the money IMO. Get rid of the headers and go with either smaller diameter headers or just return to stock exhaust manifold... or go with the Grimmspeed crossover pipes and maintain the stock diameter up-pipe. Stay with the top mount IC. If you go with a new turbo, get rid of the waste gate. It is a waste of money unless you actually need it to control boost creep. The catted down pipe isn't helping you but you should still achieve 400whp easy with it.

A "must have" are TGV deletes. Check out one of our vendors here "TurnInConcepts". They sell a composite set of TGV bodies that eliminates the need for phenolic spacers and they are a decent weight savings also and a great price. They are specifically designed for top mount injectors though. If you have side feed injectors then I recommend you perform a TGV-ectumy on your stock ones and use phenolic spacers between the tgvs and the head.

Consider some "under the hood" heat management like exhaust wrap and a turbo blanket to help keep things cool and to help manage heat soak. Another "must" is to consider cold air for your intake. There are a number of manufacturers that make cold air boxes that surround the short ram intake and draw air from outside the engine compartment. It is the single best improvement you can make... besides dumping that turbo in the garbage LOL.

***EDIT*** Also another great mod you can do is to find another tuner! I also noticed you have a 2007... I believe that is top mount injectors... is that correct?
 
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Welcome to the forum. The AMR Turbo's aren't as popular as they once were. If you're looking for a very good turbo, the Blouch Dominator 2.5XT-R is definitely great choice that's easily capable of your 400hp goal. The Dominator 1.5XT-R is within 10hp of the 2.5XT-R and the 1.5 is also $100 less. They're easily a best seller for our Subaru customers considering they're drop in, come with feed line, gaskets and they have very good life when running a high quality oil such as AMSOIL with it. We also have pretty nice discounts on Blouch Turbo's.
 

STI 2NR

New member
Have you checked out kunigawa turbos for a reliable inexpensive option? I run those in my subies and have nothing but good things to say about them. For your hp goal a td06sl2 20g would easily achieve those numbers. There is a group buy on nabisco right now, check it out. Steamspeed is the vendor I believe.
 

Td_d

Commander In Chief
I've heard good things about the kunigawas as well, guys use them here.
 
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