Hard pipe for what? I have RFLs on stock piping and they work fine, you just have to block off the recirc line.
And Stage3, yes you need 2 of them. The only problem I've heard with them is the springs getting weak after awhile and they start leaking. I haven't driven mine in awhile but when I did I had no problems and they didn't leak during boost leak tests, but I never filled it with more then 10psi for testing.
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Originally Posted by Automobile Magazine
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.