An NA cam generally isn't good for FI.
As far as keeping up with a Z28 ... if it's stock, you might be able to run with them or beat them with a full bolt on / cammed 4.6. However, once the Fbody owner starts modding his car, it's game over for any NA 4.6.
If this Z28 has a cam, then you should just buy a new car.
99 Chevrolet Camaro Z28 M6 - 6.676 @ 103 in 1/8, 10.512 @ 130.2 on street tires, H/C/I
93 Eagle Talon TSI AWD 5spd - Built 6 Bolt, 16G Evo3, HKS 272 Cams - under construction
94 Mustang GT - 5.0 bored and stroked to 347, Vortech V1 @ 10 PSI, Tremec TKO 600 - PIA