Here a very accurate map showing the Sunni areas in Iran.

What should be noted is that many Iranian Sunnis live in major Shia cities like Tehran, Isfahan Shiraz and even Mashad (that has a native Sunni minority of around 15%!). Also conversions from Shi’ism to Sunnism are very common among Ahwazi Arabs in the last few decades (a phenomenon even bitterly acknowledged by the Shia clergy and regime official more than once), so the Khuzestan province should be clustered with Sunnis, especially the western Arab part of it.