Ecotec Ported Head Wire Harnesses & Adapters Rod bearings must be purchased

Rod bearings must be purchased separately

The XPZ requires ported heads with machined valve guides

as well as the barometric sensor that sits out in the open

Most GTPs are losing between 1

patent-pending X-Digital technology that makes them the fastest responding wideband air/fuel ratio controllers in independent testing against 17 other wideband UEGO air/fuel controllers

Ecotec Ported Head Wire Harnesses & Adapters Rod bearings must be purchasedA ported head increases airflow by reducing restriction therefore more high rpm horsepower. Increasing head flow creates more horsepower at the same boost level and works very well with aftermarket cams. LSJ: All flowed at 28", 3. 5" bore plate, exh had a 1 5 8" flow tube, and stock valves (int. 35mm, exh. 30mm). Do NOT be fooled by other venders flowing heads without a flow tube, in the real world people run headers, not open heads without headers or