Well I'm going back in time a little LOL. I have a 95 Z71 with a stock TBI 305 and a chip. This engine has been awesome but I'm down to 60 PSI and it's still running. I'm going to pull it out bore it 30 over. I was thinking about drilling the provisions for a roller cam. Questions what was the difference in lift and duration from the hydraulic cam vs the roller cam 87-95? Why is roller cams so much more expensive than the hydraulic? Can someone point me in the direction of a good camshaft for Towing from 0-4000 etc in the roller and hydraulic that doesn't require modifications? I already have good exhaust etc? Thank you for any and all input.