ok i have a 91 z28 just wonderin if the factory cam from the original 305 tpi was only specified to work with the map setup,also im putting in 89 k5 5.7 which i know is not a roller engine would this motor work fine with the map sensor also i have a stage two chip dont know if that helps any advice?

As far as I know all 91 comes with the MAP, my differently does.