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I put Shell V-Power in mine and it pops as it should. Give it a bit more time to "run in" and remember that both engine and exhaust have to be in Sport+ (in case you didn't know). Also don't expect pops and bangs under 5k RPM. They do happen but not as often as over 5k RPM.
Easiest way I get a triple shot out of mine is by downshifting (Rev matching ON) from 3rd gear at 4k RPM to 2nd gear at ~5k RPM.
While at 5k RPM give it a little bit of throttle and release. Repeat to get infinite pops and bangs (don't do it too often unless you want to test out the i10 courtesy cars )