8 to 1! What are you going to turbo it or something? Are you sure? Why would you go to all the time and expense of putting a cam in a motor that has that low of compression?
Anyway the Rhoads will smooth out your idle but give you full lift off idle. The trade off is they are usually a bit noisey to the point that you might think something is wrong or just get annoyed by the sound after awhile. I had a set of Rhoads on for a short time but it smoothed out the idle so much it sounded like a Toyota to me( exaggeration ).