What kind of shocks?

I'm looking for a smooth ride, and not racing suspension, but want to protect the existing springs.
V8 bars and springs will go a long, long way to making a sure footed more modern feel to the ride without being harsh. in fact you can go fairly heavy on the spring rates with good shocks before ride quality suffers.

anyway, i don't understand the statement "protect the existing springs"? can you explain?