Stage2 Upgrade:
-CatBack Exhaust-

Getting exhaust out of the engine is the 2nd key to producing power. By reducing the restriction of gasflow in the exhaust system, less crankshaft power will be used during the exhaust stroke. This will allow more power to make its way to the wheels. In addition, this benefits turbo spoolup as exhaust restrictions create a pressure barrier after the turbine that lessens the power delivered into the turbine wheel.

Stage2 Upgrade: Pricing and more info:

Stage3 Upgrade:
-Engine Control Unit

The Engine Control Unit (ECU) is a a small computer which monitors all engine sensors and controls all engine functions for fuel delivery, ignition timing, rev limiter, speed limiter, valve timing control and emission systems. This computer operates based on a set of values of which Nissan generated in their development process of the powerplant, however, they left a lot to be desired by the enthusiast. The ECU upgrade consists of the removal of the stock program chip and the installation of a socket which allows for quick and easy installation/removal of the EPROM memory. A new program catered to optimizing your vehicle's modifications is generated and installed.

** 15psi suggested maximum boost level! Exceeding this level almost guarantees engine damage with stock injectors!

The ECU upgrade is a critical stage3 upgrade. Intake or exhaust can be installed in either order, but the ECU upgrade is a necessary 3rd step in order to maximize the potential of the parts installed.

Even though you will likely be using boost jets to increase your boost level, the stock boost guage is incredibly inaccurate. It is strongly suggested that you purchase a boost guage and a-pillar pod to ensure you boost level is where its supposed to be. (15psi max).

Stage3 Upgrade: Pricing and more info:

Stage3+
The addition of an underdrive pulley in conjunction with an ECU upgrade will do wonders for both the 'seat of pants' difference as well as real power output. Both non-turbo and twinturbo Z's will notably benefit from the installation of this upgrade.

Stage4 Upgrade:
-Downpipes & Testpipes-

This upgrade is an extension to the stage2 exhaust upgrade. By eliminating the restrictive precatalytic downpipes as well as the restrictive midpipes/main catalytic converter and replacing it with larger diameter, mandrel bent piping, you will greatly enhance spoolup performance of the turbochargers as well as free up more power. Our downpipes include additional O2 sensor bungs for installation of wideband O2 sensor setups!

Stage4 Upgrade: Pricing and more info:
Downpipes
Testpipes

Stage4+
At this point you will be generating enough crankshaft torque to begin superceding your clutch's capabilities. A clutch/flywheel and 1-piece driveshaft installation would be a timely upgrade as the transmission has to be removed to install these downpipes. See our selection of driveline upgrades - you can check those products out HERE.

Stage5 Upgrade:
-Injectors-

When upgrading to higher power levels, stock fuel injectors are short lived as they simply cannot delivier enough fuel to safely run more than ~380RWHP. At this point in the upgrade path, even with stock turbos your car is now capable of outflowing the injectors. Upgraded injectors are engineered and designed to flow larger amounts of fuel to keep up with the demand as airflow increases. Injectors are precision made and have exceptional calibration directly from the factory. Available in 555cc and 740cc flowrates from Nismo, and 850cc and up from other companies.

Stage5 Upgrade: Pricing and more info:

Stage5+
Since you now have the ability to flow more fuel, you can also raise your boost level. It is recommended at this point to install an electronic boost controller rather than trying to use smaller boost jets as a boost controller will more accurately control your boost level as well as offer enhanced spoolup of your turbochargers. We also recommend the use of a turbo-timer to allow for proper cool-down of your turbochargers as they will be generating more heat with increased boost levels. You can check out our performance electrical upgrades in this link.

Stage6 Upgrade:
-Intercoolers-

While the stock intercoolers have supported you up to this point, they have now become the next limiting factor. Upgrading this component will allow you to run more boost and flow more air with less pressure drop between the inlet and outlet of the intercooler. Since the following stage upgrade is larger turbos, it would be wise to go with an intercooler setup, beit a sidemount or frontmount intercooler setup, it needs to cater to the power levels you intend on going up to.

Click on images to the right for description of intercoolers pictured, as well as pricing information.

This is the last of the major upgrades that fall into the category of upgrade steps with stock turbochargers.

Click image to right for description page>

Stage7 Upgrade:
-Dual Intake-

At higher boost levels, the stock turbos do become restricted by the filter itself. This restriction causes them to have to spool faster to produce the same pressure, and it also limits the peak boost pressure they can achieve. In addition, the stock Mass-Airflow sensor is only capable of metering about 550RWHP. Although this isn't going to be a limitation with stock turbochargers, the restrictive element of the filter will reduce the amount of power you can generate with stock turbos as well as affect spoolup.

The addition of a dual intake setup reduces the restriction of pulling air into the turbochargers as well as increases the maximum meterable intake air by 2X. It has been found with a stock turbo equipped Z to add an additional 10RWHP and 10RWTQ at the 400RWHP level as well as increase spoolup by a few hundred RPM. The maximum boost also creeped up another 1-2psi.

Staged upgrades from here....

At this point you have just about maximized the ability of the stock turbos to produce power short of internal engine modification. Your Z will certainly be capable of producing 400-415RWHP with proper tuning and race fuel with boost pressures around19psi, and with proper traction you can easily run 11-second 1/4 mile times. Since the next step in the upgrade list is larger turbochargers which will require an engine pull to install, there are a few bolt-on options available to perform while you have the engine out of the car without disassembling the engine.

However, if you are shooting to build your Z well past the Stage7 level or you have a higher mileage engine, building up the engine using forged pistons, larger cams, stiffer valve springs, portwork, and larger valves are all options you have in front of you at this point. We do not consider modifications past this point as a 'stage' upgrade because any one of them being performed will add to the ability of the engine regardless of if another engine modification is done - it really becomes more a matter of 'how much power do you want and how much money are you willing to spend'.

Stage8 Upgrade:
-Turbochargers-

There are a multitude of different turbo kits that are available from a large number of different manufacturers which range from making 400RWHP to 600RWHP level and have reasonable spoolup characteristics for street use. Just remember, the more power a turbo is capable of making, the more 'laggy' the boost response is going to be, but there are other modifications that can be made during the installation of turbochargers of which will ehance the spoolup characteristics of the turbos.

We have a lineup of turbochargers of our own that we have developed specifically for the Z32. These turbochargers currently range from the 400RWHP level to 600RWHP level, but with the addition of the "NFA Kit" used on "The Peacemaker", we are spreading that range into the 800RWHP level.

Exhaust Manifold Upgrade
While you have your engine out for your turbo upgrade, now is a good time to consider doing something with the exhaust manifolds. Since the engine is simply an air pump, getting air in and out as easily as possible always benefits the production of power, turbo spoolup characteristics, and engine efficiency. Porting the stock exhaust manifolds will prove to be beneficial as they are highly restrictive in their native casting and prove to produce appreciable constrictive losses above the 500RWHP levels.

Going to tubular exhaust manifolds will greatly reduce exhaust restriction between the cylinder heads and the turbine housing of the turbocharger. This will produce a quicker spoolup characteristic of the turbochargers as well as allow the engine to put more power to the crankshaft because of the lower backpressures associated with this design. The manifolds pictured are made by SpecialtyZ and are constructed from inconel. We have used these on several occasions and have seen an average of 50RWHP increases as well as phenomenal turbo spoolup.

The Greddy TD series turbo kits come with their own tubular stainless steel manifolds as the turbochargers are manufactured by mitsubishi and they have a different turbine housing flange of which does not bolt-up to stock exhaust manifolds. Those kits range in power output from 550RWHP up to the 700RWHP level.