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Subaru EJ20K turbocharged

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Hello there , second vehicle that i am going to tune. It's a subaru ej20k turbo charged with a stroker kit 2.2L. My question is what would be the ideal AFR for 1.7 bar (23psi,230KPa) boost.Tuning on a Power Fc and saw the previous tuner map tuned it up to 9.83 af isn't that bad?. (98RON fuel european.)

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Use a wideband to help you with actual a/f ratios, don't assume the table is 100%. In general lambda 0.67 or AFR 9.83 is awefully rich for pump gas.

Thanks Andy i will you use my wideband to make sure table is 100% .What should i target at WOT? Somewere 10.8?

G'day Fotis.

Can't give you a solid number to shoot for as you need to determine what the motor really likes when you're tuning it. That's a decent amount of boost, I'd be looking at mid 11's (~0.8 Lambda) to start with, and adjust from there. Are you tuning it on a dyno, or on the road?

9.83 is really, really rich, but without a wideband you can't know that's actually what its running. Might just be the numbers the last tuner put in there to get it running at the AFR he actually wanted. She'd be a bit smokey on power running that rich! :-).

Hello Zac, I am road tuning the vehicle , i am planing to do a test run before i start changing the previous tune. That's what i though but is it possible because of the boxer design of the engine to run that much rich? Also in the Fc edit software for boost control having the 1st one checked means the car will run 1 bar of boost?

Thanks :)

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I've never had to run an engine excessively rich because it's a boxer, so I'd say no. A common subaru issue is that they rely heavily on the OEM knock control system in stock form, which leads to detonations and bearing failure with only light modifications. Its possible the original tuner was trying to run the engine really rich to mask this? If you do a proper job of tuning the ignition table this problem goes away.

I havent used the FC Edit software or a datalogit (I'm trying to buy one, but cant get a response from them!), but from your picture, it looks like that option will set the boost target at 1.0 Bar, yes, but its got a fixed but value, so I don't think its a closed loop control system.

The owner of the vehicle told me that he has issues at Wot were close to rev limit sees knock, If the previous tuner did so to mask the detonation then this is very wrong approach he should just retard the ignition.

The problem with the boost target is that since it's at 1 bar the vehicles runs 1.6( seen from an external boost control) and i don't know why, it should stay at 1 bar ... Power Fc software kinda unfriendly to user or just me haven't learned it yet haha :D

I find almost all tuning software is really hard to use until you've got some experience with it, don't even get my started on Pi-Caltool!

I think where the FC-Edit software has the labels 1.00, 1.10, etc, they might just be arbitrary names given to the different options and not actually used in any boost control math anywhere. The boost level the car ends up running is determined by the value in the 'duty' field, as this is the duty cycle the control solenoid will be pulsed at?

I'd try removing the boost control solenoid from the system, and plumbing the wastegate directly to manifold pressure. This will let you know the absolute minimum boost the car can run. Then you can add the boost control solenoid back into the system and work from there.

Awesome thanks Zac , as for the solenoid we permanently removed it :D

My EJ207 runs good at 11.2 up to 2bar.

What size injectors are fitted? They may not be able to reach that target of 9.

I think they are 750cc haven't checked yet

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