You're building up over time, so stuff is going to break on your car. At best all your hoses are 10 years old, at worst 16 years old. So really, see my above post. Once you've done what I mentioned above, post up pics of your very nice Z then get to doing things like new turbos. I forgot to mention you'll want a new cluch eventually.
"The 300ZX Turbo is a dance; it's a song; it's rolling, roaring automotive art. There is no color that doesn't suit it. There is no mood-lifting chemical substance it can't replace." - Automobile Magazine