Features include: 347 Stainless Steel Alloy is used for valve and valve housing. High temperature silicone Nomex reinforced actuator diaphragm 17-7 PH stainless steel actuator spring gives consistent pressure at high temperature; resists "relaxing" at temperatures to 900F (483C) Nitronic 60 stainless steel is used for the valve seat and valve bushing - the same material used in the higher level gates for reliability and longevity Wastegates shipped with air fittings and stainless hardware.
The TiAL 38mm is the only wastegate with the option to choose the valve stem's protective coating. To keep the overall cost of the unit down, the choice was left to the customer. Lead Oxide which is present only when burning leaded fuels is corrosive to the Black coating on the Street valve's stem. Extended use of leaded fuel will cause performance problems and unreliable valve actuation. The Silver coating on the Race valve stem is resistant to the corrosive effects of Lead Oxide. Similarly works well with unleaded fuel. The Racing valve is available for an additional charge.

Please consult the spring chart above to see which spring is the one you'll need for your desired boost level.  This spring determines your minimum boost pressure.  You can use a boost controller to increase boost from there, but we do not recommend going past double the spring pressure for your max boost level.