Zulu and Nkumane have signed on a permanent after being allowed to leave Pirates while Thabo Rakhale and Linda Shiba are on loan from the Bucs with Ayanda Ndlovu also arriving on loan from Maritzburg United.
Sivutsa have also strengthened their squad with Tshepo Bulu, Edward Williams, Curtis dos Santos and Sherwin along with Guinea born defender Sylla Mbemba all of whom have previous PSL experience at different clubs.
"We have assembled a squad that we feel can compete amongst the best this season," says Charles Nkosi, the Sivutsa spokesman.
Fellow First Division campaigners Blackburn Rovers have snapped up Morgan Shivambu on loan from Platinum Stars while also signing former Bay United striker Lungelo Yekiso.
The trio of Khethukuthula Nxumalo, Tebogo Mohlabani and Mosebo Sabata have joined from Carara Kicks.
FC Cape Town have appointed new coach in Nigerian Paul Aigbogun who has previously coached at Warri Wolves.