hatch sti sc46 problems
 

hi guys not posted on here for a long time as I've been out the game but im back haha,I've got a forged hatch sti which was running 340/400 on standard turbo no problem but I've recently changed to a sc46 turbo,1000cc injectors and perrin 3port,nothing else has been changed,right I've got the guy who mapped it when it was standard to come and do it for me again BUT he is having issues with flat spots throughout the rev range and the car just not driving nice but the main problem is boost creep (massive) he cant seem to control the boost its still on a top mount which I am about to change but it boost to around 1.5bar and then as the revs rise the boost climbs and I mean a lot (2.0bar+) the car doesn't feel quick and this has been going on for a few weeks now,he has offered me a refund which is fine but im not sure what to do im left scratching my head lol I've recently learned that these hatch sti ecu is very complicated so im wondering if he's just struggling with turbo/injector upgrades on that ecu?can any of you guys maybe give me some advise on what to do or where to take it?many thanks matt

was the turbo new? Whos mapping it?

turbo had covered 1k when I bought it and don't wanna say who is mapping it but he's a well known mapper in the Subaru industry

Go to a different mapper. A good mapper should be able to point you towards the issue and recommend a fix or even help to fix it. If the mapper keeps struggling and doesn't understand the reasons why then it doesn't inspire confidence.


Have you taken the car to a Subaru specialist for their diagnosis?

yes taken to my local specialist where they fitted the parts and they said the car is mechanically perfect?its a mapping issue but not sure where to take it now lol

i take it you ruled out cracked wastegate/faulty actuator/faulty solenoid/leaky vac pipe by just running wastegate pressure to begin with? The hatch ecu certainly has a load more going on than the hawks - if your running open source there will be a few useful tables you can't see (though you can work around it a little by changing other tables).

On the injectors, are you running a fuel regulator with them or just straight off the standard rails/pump. Have you done the "gr stumble fix"? There's a physical change to the fuel pipes in the engine bay along with tweaking the map.

Quickie
 

I had exactly the same spec..

Added Grimmspeed boost solenoid, Perrin CAIK and inlet hose on a tmi.

Went very well 😃😃

You're best checking tmi piping esp the one underneath (have to take it off) and get some proper clamps not jubilees.

Had mine mapped by Martyn at Enginetuner. He's seen many of these.

Good luck 😃

yes ran waste gate pressure to rule out problems,the injectors are straight off the rails im not running an aftermarket FPR?this car never missed a beat b4 all of this lol

all checked mate and all ok :thumb: i might give him a shout cheers

Hi matt hows things? Its si. Heard you got a hatch lol you managed sort it yet?

Bloody hell hello mate u Ok?nah not sorted yet I've not touched it in 3 weeks lol

Lol yea im good mate just very busy at work and with the kids. Ill drop in on u soon

Pm sent mate