It has 8 independent ports and benefits from the inertia build up to improve engine torque at low and medium speeds by closing 4 ports below a certain RPM and throttle position to increase air speed and maximize fuel atomization and opening all 8 at higher engine loads for better air volume. Air metering is through an air flow meter and there is no factory BPV/BOV in this generation. Fuel delivery is through 430 cc injectors while air is fed through a throttle body and intake and exhaust valve lift. Compression ratio is 8.5:1 and produces and with a factory 8-9 psi of boost. Fuel cut is at 12 psi. Second Generation The second-generation Toyota CT26 used a twin entry turbine housing with dual wastegate ports. It was fitted to the second generation Toyota Celica GT-Four (ST185) as well as the Toyota MR2 Turbo (SW20). The intake charge is cooled by an air-to-air intercooler either top-mounted in the Celica or side-mounted in the MR2. The rally homologation Celica (known as GT-Four RC in Japan, Group A Rallye in Australia, or Carlos Sainz Limited Edition in Europe) used a top-mounted water-to-air intercooler and is distinguished by a hood vent rather than a hood scoop as found in the non-homologation ST185s. This generation retains the T-VIS intake manifold and the Air Flow Meter. A factory BPV is included in the SW20 MR2 Turbo but not on the Celicas. Compression ratio is 8.8:1 and produces and . This generation retains the injector size and throttle body size from the previous generation. However, boost is increased to 10-11 psi in the ST185 and MR2 while it is increased to 16 psi in the ST185RC. Intake and exhaust valve lift is significantly increased to . Third Generation The third-generation engine uses the Toyota C20b turbo, which was of the same design as the second-generation but with a slightly improved turbine housing and larger compressor wheel. A factory BPV is installed on all applications. The intake charge is cooled by a water-to-air top-mounted intercooler similar in shape to the ST185RC WTA. One can tell the difference as the ST205 WTA is black while the ST185 WTA is silver with a black centre. This generation does away with T-VIS and uses a normal 4 runner intake with the same port shape and size as the NA engine (but with larger injector holes for side feed). The Air