It fixes the front two cylinders getting less airflow than the rest.
They range between $180-250 I believe.
http://www.motordyneengineering.com/350z.asp
http://www.alteredatmosphere.com/350z/350z_2.asp
(bottom of page)
Yes you can still use the stock bar with either of them.
I believe they require you do use spacers and longer bolts however.
Everything you need will come with either of them.
It's the next logical mod IMHO.
(Other bang for buck)
After that would be an exhaust with or without high flow cats/test pipes. Headers will also increase power, but are pricey to install. So, bang for buck there is hard to say... But you can get an exhaust from $650 to $$$$. So bang for buck is possible. Plus a different sound. (IMHO, the stock exhaust sounds fine)
Then look at an ECU reflash from either AAM (alteredatmosphere) or TechnoSquare. (more bang for buck 5-15rwhp for $600 but helps keep your ECU from taking that little bit of power you lose over time due to the ECU keeping emmisions happy, from all those mods you just added.
TS (technosquare) says they alter the "correction factor" to help keep the ECU from "adjusting" from the mods over time. They also change the throttle body opening from 80% to 100% after 5500rpm.
My recipe for a fun, fast, reliable Z.
(Hotchkis TVS system is also in my Bang for Buck category.. springs and sways for under $400sale price)
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