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Shift Knock- Built Subaru

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I've been working on tuning my 2005 Legacy GT for a while now. I have a pretty solid feeling tune that pulls great and drives smoothly. However, when shifting hard the car pulls sometimes up to 11 degrees of timing. I have been trying to clean this up by retarding timing and messing with tip in enrichment but I can't seem to get rid of these knock events. The car was previously pro-tuned and does not pull timing or log knock events during shifts (But on their tune does knock in high gear, high boost!) The car has a Blouch 3.0xtr and an IAG stage 2.5 block with ID1050x Injectors. Still running MAF. It also has D25 heads instead of the B25s that came in the car.

Have you actually confirmed whether the knock is actually real by using audio knock detection? I'd suggest starting there as it's not uncommon with a built engine to change the noise profile enough that the ECU picks up false knock. Some aftermarket ECUs offer the option of tip in retard but from memory I don't think that's possible with the stock Subaru ECU.

I have a similar setup with a cobb accessport on a 2.0 that uses speed density and retains the MAF. If you have the stock ecu you can setup the knock activation thresholds with load and RPM. The Feedback knock correction table should show you where that is occurring you would just need to be careful that you dont clip out portions of the load range where you want it to be active. There are also some load delta disables you can play with. Like Andre said though you want to confirm what you're dealing with before getting the ecu to ignore something.

Thank you for the suggestions! I do not have knock detection equipment but during this time of quarantine I plan on building a set. I believe the subaru knock range is around 5.6kHz? Any other suggestions for a diy set?

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