No additives needed on roller lifters, as far as do you need a solid roller cam or what the benifets are , how much power do you want to make? I have one custom ground solid roller cam that is really stupid as far as how high in RPM it will pull hard to It made peak HP on a engine dyno at 5600 RPM, the car goes faster if I shift the motor above 7000 RPM I missed a shift point in the car the last time out( it was dancing around a little on the back tires, the fronts where in the air ) and the playback tach shows I shifted it out of first gear at 8100 RPM, it was still pulling hard I've had a lot of race and street motors with solid flat tappet(lifters) cams, none of them like to pull hard above 6500 RPM