question about upgrade on my engine

[Just another 240]

i'm planning to upgrade my engine by adding a turbo.

I know i have to or at least should lowering my compression ratio. My question is that how can I ? My friend said that i can do it by adding a slightly thicker gasket (let say i do it that way)but then how can i know if i lowered my compression ratio too little or too much by the gasket.Does it label on the gasket? or what?

Also if i do add a turbo, do i have to change internal parts(piston, rings etc) to withstand the power of the turbo so things wont' start breakin on me.

[Just another 240]

Let's say I go the other way and tried to lower my compression ratio by buying new pistons, then how do i tell? does the piston come with labels saying how much it would lower and stuff?

[GodDrivesA240sx]

Let's say I go the other way and tried to lower my compression ratio by buying new pistons, then how do i tell? does the piston come with labels saying how much it would lower and stuff?

Well the 'search' button comes with the answer to this question

You buy the pistions, they are rated at different ratio's, that's how you know. I believe you need to buy 8.5:1 but you really need to do more than that to the engine if you're going to turbo it. Unless you plan on running low boost, and even then it won't last that long if it has a lot of miles on it. I suggest you rebuild it.