We haven't got as far as we had previously promised. Project Z still hasn't made its date with the dyno, but there's a good reason. Building a 350Z to properly support the power and meet the lofty goals we've set requires a significant amount of hardware-too much to mention in just one project car installment.
As we dream of building the poor man's exotic-killer, the story of Project Z's construction is best told with a somewhat corny analogy. When building a house, it's important to start with a strong foundation. If the project car we're building is to hang with the venerable Corvette Z06, it had better be one stout brick. We did just that in our last installment of Project Z, when we went through the engine's long block with fortified components to ensure reliability under boost.
Our built engine with Pauter rods, JE forged 8.5:1 pistons and a JWT turbo kit is all dressed up and ready to go, with all the coolant and oil hard lines-as well as the turbo vacuum lines-already plumbed.
With the engine's internals squared away, we turn our attention to the all-important peripheral ancillary components to achieve our goal of 500 wheel-hp and Z06 humiliation. After rescuing the Z from VRT's shady clutches, it was readily apparent that it had been turned into a sad basket case. Extensive work from a crew with plenty of competent mechanical skill was needed to put our project back on the road.
The car and assembled engine were brought to Steve Mitchell and his team at M-Workz in Gardena, California, for final assembly. The staff at M-Workz includes ex-personnel from Nissan's engineering department, who chose not to make the move when Nissan relocated its North American HQ from Southern California to Tennessee. Mitchell is also well-versed in aftermarket work on 350Zs, G35s and all sorts of GT-Rs, as well as racing one of the fastest time attack Zs on the continent (see page 38), powered by a larger version of the Jim Wolf Technology kit about to go onto our Z. Who better to work on our car than the people who helped bring this to fruition?
The JWT 700 turbo kit uses Garrett's famous GT28RS 'Disco Potato' turbocharger (left), compared to the smaller GT25 unit in the base Sport 530 turbo kit (right).
Turbos
The critical component in the equation is turbocharging. Jim Wolf Technology provided one of its complete turbo set-ups. The JWT 700 system, (700 for 700 wheel-hp) is noted for its OEM-like attention to detail and completeness, as well as performance.
Our kit came with JWT's Sport 700 turbos, which are based on Garrett GT28RS ball bearing turbos, otherwise known as the famed 'Disco Potato'. Compare that to the base Sport 530 kit, which uses smaller GT25 turbos. In theory, the 530 kit is capable of the 530 wheel-hp we're looking for, as long as the fuel system is sufficient and the bottom end strong enough. After consulting with JWT, we decided on the relatively quick-spooling 700 kit for the additional headroom, and the more progressive and track-friendly power delivery.
The cast O2 sensor housing divorces the wastegate and turbine discharge ports with this cast and machined boss. Separating the two flows adds power and increases spool, since it reduces backpressure, as well as flow interference/turbulence when the wastegate is open. Ideally, flow is re-merged over six inches downstream, but in order for the kit's O2 housings to bolt up to the stock cat locations, the housing was cast to merge the flows earlier.
The Disco Potato features a 60-trim version of Garrett's ultra-efficient BCI-18 compressor wheel, contained within a T04B housing with just the right diffuser width for maximum adiabatic efficiency and a wide map. The turbine is a 76-trim, nine-blade NS111 wheel, known for its efficiency at converting hot exhaust gasses into shaft power. This allows the use of a large, free-flowing 0.86 a/r turbine housing.
The turbos' oil and coolant feeds are all plumbed with hard lines and all charge pipe couplers are heat-resistant, multi-ply silicone. During the build process, our block was modified to have oil return ports drilled into the lower sump so that turbo drain oil dumps in above the oil level for minimal restriction. JWT supplies a sump sandwich plate with the kit that adds one additional quart of oil capacity as well as return nipples that sit below the oil level. We plugged these up.