Hello, first of all I am working on a sbc 350 with vortec heads, dished four valve relief pistons. Comp xe268 cam .477 .480 lift, 1.5 roller tip rockers on intake and 1.6 on exhaust. After I put the motor together and installed it in my car I tried to start it. After a few minuets of messing with timing, trying to get it to start I noticed gas pouring out my exhaust. After that, I discovered that I needed a fuel pressure regulator. After I installed one I tried to start it again. With no luck I pulled the valve covers and found most of my push rods bent. I'm trying to figure out how they bent and how to prevent it from happening again. Bty the motor never ran. It was just the starter turning the motor. Is it possible I have a bent valve. Could have my piston slapped a valve?