I just busted some valves when I was taking the valve spring off. The keepers kept breaking the tops off the valves. Anyway, I have no choice but to get new valves so I am going to get aftermarket valves

I was looking at Supertech and Skunk2 valves. Are there different sizes to the valves? I know that you can get valves that are oversized etc, but when I was looking at some Supertech valves they also had different lengths.

I'm a bit clueless on valves, I searched the archives and didn't really find much info.

Can anyone chime on some valves that would be good for FI applications that are stock sized and will fit like stock?

The setup is a complete STOCK D16z6 head.