My grandfather is saying its hydraulic,but I've been told it uses a roller cam. Is it by chance a mix of both? Sorry for the stupid question.

It's a hydraulic roller. It has hydraulic lifters with roller tips. The roller tips ride on a roller cam.

So we're both right. Thank you

Yep, if it's the factory camaro engine, it's a hyd. roller cam.
Your granddad is thinking flat tappet cams (non roller) hyd. or solid

Ok that's sorta what I thought he meant,but it's hard to argue with him without having any proof. Thank you.