There are two factors that will allow the ECU to advance timing, IAT and knock. First you have to be able to datalog the timing and IAT out of the OBD port. If you can't, it's a bit harder.

For the knock test, put some 100 octane race gas in the car. Log the timing during some full throttle runs and aggressive timing. Then go back to 93, and do more datalogging.

The IAT is a bit more difficult. Try to drive the car when it's very cold out for your area. Start the car and once the coolant is OK, log the timing. Then get the car hot, possibly in stop and go traffic in heat, then log the timing again. You should get some decent timing numbers to see what the ECU is doing in different heat load/octane scenarios.

Now, if the numbers look good, then see if you have an IAT sensor that the jet can blow past and this will help. If you have a MAF before the turbo with the temp sensor integrated, you will only be able to affect the knock with W/M.

Hope this makes sense. I have seen over 10 degrees of timing change in some cars so even if the ECU is locked you can see large benefits.