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Old 05-24-2019, 11:15 AM   #1
Scooby Newbie
Member#: 476198
Join Date: Oct 2017
Default Looking For Some Tuning Expertise

Hey guys,

Itís been quite a while since my last post, and I do much more research here rather than posting. But I need your help here.

Quick Mod List (Thread Relevant)

-Fresh VF39
-Walbro 255
-Samco silicone couplers
-Silicone Inlet
-Catless Uppipe
-Full 3Ē TBE
-AEM Wideband/Boost/Oil Pressure

Real quick background. I purchased a 2005 FXT 5MT about 3 years ago. Long story short, I bought it ignorantly with bad headgaskets and ringland failure. I had the shortblock completely rebuilt by a local machine shop. I also addressed any underlying issues such as installing all new vacuum lines, replaced the wore out factory turbo inlet with a silicone replacement, all new mls grimmspeed exhaust gaskets etc. After the rebuild and refreshing of the engine components, I began to enjoy some spirited third gear pulls once in a while. Whilst doing so, I grenaded 3rd gear around 5k rpm this past November. I had sourced a JDM SF Forester turbo 4.44 pull style transmission over the winter and picked it up just out of state. Made the appropriate changes to make it work (Different VSS, Female Axles, Different Reverse/Neutral switches etc.) It seems the car has been down more than itís been up. But believe it or not, thatís fine with me. I love working on it just as much as I do driving it. I just want it right.

So advancing to this present day, I just got the FXT back on the road. All new Legacy GT brakes, slotted/drilled rotors, 2011 WRX wheels, looking and feeling great! JDM transmission shifts well and feels good! Engines running great! Hereís my dilemma...

After a week of just driving back and forth to work, seeing minimal boost and rarely anything above 4k rpm... I grew the balls and decided to do a third gear pull this morning. Ambient temperature about 60F. Relatively high humidity because well... Michigan. Anyhow, so I do the third gear pull from 3k rpm to about 5800-6k. Car pulls like a raped ape. However, it maintained an AFR of about 10.0 to 10.3sh and I even seen it dip into 9.9 for a split second. To me, this seems very rich. And my main concern comes in here...

During the pull, I could hear a tinging, like very slight metallic rattling. So obviously as you can imagine, my concern is potential spark knock/detonation. Now, from personal experience with other vehicles, I always noticed a power loss during detonation/knocking. I would imagine that if this engine was actually pinging, I would notice some sort of power loss. Either that, or if it were actually pinging/knocking then Iíd think Iíd get a CEL and power/boost cut. But I could be dead wrong, and donít want to find out the hard way.

So hereís what I need. I will self admittedly state that I am completely ignorant when it comes to tuning. But I know that plenty of you here tune and dial in your own cars. What Iím looking for is someone to please take some time and help me. I will pull the trigger and invest in a tactrix cable. I will acquire whatever software thatís needed. And I will follow instructions to the T, as to how to log and what to log.

I basically just want someone experienced to help me log the proper parameters, and get them to you so you can analyze them to distinguish if my current tune is safe and/or if thereís any red flags. Whether it be injector duty cycle, maf scaling, timing advancing/retarding... I have no idea. Those are just parameters/terms Iíve come across while researching. I am an electrican/panel builder for a small company in which we build small custom machines, upwards to fully automated assembly lines for custom countertops/laminate. I can assure you that if youíve taken the time to read up unto this point, that I am competent enough to follow instruction and I wonít waste your time.

If anyone has any advice and/or is up to the task, Iíd greatly appreciate the help.
SoulSoak is offline   Reply With Quote
Old 06-04-2019, 08:08 AM   #2
Scooby Newbie
Member#: 457242
Join Date: Oct 2016
Location: MI
2004 Forester XT


You need to get a tantrix Openport 2.0 and take some logs to see what is going on. Download RomRaider and EcuFlash. I ended up going to COBB as there are not enough tables defined for my ECU so I have a spare tantrix I might be willing to part with. I also live in MI and have a built 04 xt MT. I am not a tuner. I did tune my own build. Send me a PM if you would like some help getting started. If you are serious about learning more about your engine management there is a lot of information out there just waiting for you. The RomRaider site has a ton of information.
Burkwerst is offline   Reply With Quote
Old 06-19-2019, 11:29 AM   #3
Scooby Newbie
Member#: 476198
Join Date: Oct 2017

Thanks for the reply brother! Sorry I'm a couple weeks late in response. Been extremely busy. Currently at the hospital awaiting the birth of my first son (only took 3 daughters to get here lol).

I will pm you and greatly appreciate your willingness to help!
SoulSoak is offline   Reply With Quote
Old 07-20-2019, 11:23 PM   #4
Scooby Newbie
Member#: 149442
Join Date: May 2007
Chapter/Region: RMIC
Location: Colorado
2014 WRX


You are not going to audibly hear engine knock. More likely you're just heari g something like a heat shield rattling or such. That is pretty rich. Start with doing a boost leak test and go from there.
Impaled is offline   Reply With Quote

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