(2) Boost Jets with .038 inch orifice.
These boost jets or orifices are installed inside each of the rubber lines going to the two wastegate actuators on a 300zx Twin Turbo. Restricting these lines, that have pressurized air running through them while the car is under boost, decreases the pressure acting on the wastegate actuator which in turn raises the boost level that the turbos produce. These boost jets are not to be installed with-out the proper ECU upgrade and/or tuning. The maps in the ECU must be adjusted to accommodate for the higher boost levels without the chance of detonation which can result in extensive engine damage. Installing boost jets also requires installing an external boost gauge to be carefully monitored capable of measuring boost accurately and over 15 psi.
A stock 300ZX Twin Turbo produces only about 10 psi of boost pressure. The orifices in the boost jets sold with the popular JWT ECU upgrade are around .040" resulting in about 12-13 psi of boost. The boost jets presented in this listing are a bit more aggressive with a smaller orifice, however they are "adjustable" by simply filing out the holes with torch tip cleaners the boost can be dropped down to a level is safe for the particular application. Installing these boost jets with the existing .038 orifice raises the boost on most cars tested to 15 psi. 15 psi is the max amount of boost we recommend running on a 300zx Twin Turbo with stock turbos, stock 370cc injectors, and 93+ octane fuel (RM/2) with the proper ECU mappings and attention.
Many cars behave differently and installing the same boost jets can result in different boost levels for each car. Prior to installing boost jets and an ECU upgrade cars must be checked to insure basics are in order such as timing set properly to 15 degrees BTDC and that the correct spark plugs are installed. After installing boost jets it must be verified that boost levels are safe for your particular application. If you are not familiar with the symptoms of detonation and do not have access to monitoring air fuel ratios with a wide-band oxygen sensor we do not recommend installing these boost jets. Safe boost level will vary depending on may factors including fuel quality, fuel supply, altitude, existing power-plant modifications, and many more. Install boost jets at your own risk. Any damage done to the power-plant as a result of excessive boost is the sole responsibility of the customer. These boost jets are produced to provide boost levels on the higher side of what is safe for most Z32s with stock fuel injectors. They are produced this way because the orifice can be made larger to decrease the boost but you obviously can't make the orifice smaller and increase the boost should that be desired. These boost jets are intended to be adjusted to the proper safe boost level for each particular application. Install and use at your own risk!