Currently, IHI RX6B turbochargers are readily available from Power Enterprise and A'PEX Integration. There are four different compressor options available and a total of seven different A/R turbine housings.
All of the IHI RX6B turbochargers rely on the same RX6B turbine wheel. This 84.5-trim exhaust wheel has a major diameter of 62mm and a minor diameter of 57mm. The turbine wheel is housed in an ultra-lightweight turbine housing. The turbine housing has a unique RX6B footprint that's roughly the size of a T25. What the turbine section lacks in size, it makes up for in efficiency as this driver has seen flow rates that allow for over 600 horsepower.
In motorsports, weight is the enemy and apparently IHI spent a good deal of time to make the RX6B series as light as possible. A complete TCW77-P18 turbocharger tickles the scales at just 12 pounds. If you compare that to any other turbo on the market, you'll probably find it to be about a half to two-thirds the weight of a comparable-flow turbocharger. In addition to being lightweight, IHI also designed the RX6B series to be extremely reliable. On two occasions, we have had the intercooler pipe come off of one of the two turbos on our GT-R while on the dyno. While this would cause most turbochargers to overspeed and snap a shaft, the RX6B turbo wasn't even damaged.
Since the RX6B series of turbocharger does not have a water-cooled center section, installation is easier than water-cooled alternatives. As with any non water-cooled turbocharger, we highly recommend a quality synthetic engine oil to reduce the possibility of oil coking on shut down.
The smallest compressor available in the IHI RX6B family is the TCW15. The TCW15 uses a 78mm outside diameter compressor wheel that has a 54mm inducer. This equates to a 48-trim. This compressor provides best efficiencies in the 1.3 to 1.8bar (19-26psi) boost pressure range. As for horsepower potential, the TCW15 is best for applications in the 400 to 440 flywheel horsepower range.
The TCW10 compressor also shares a 78mm outside diameter compressor wheel. However, the inducer of the compressor is 59mm (a 5mm increase from the TCW15). This produces a 56-trim. This compressor is best suited for lower boost applications. The best efficiencies are in the 1.0 to 1.5bar (14.5-22psi) boost pressure range. As for horsepower potential, the TCW15 is best for applications in the 450 to 500 flywheel horsepower range.
The TCW76 compressor uses a compressor wheel with a larger major diameter than the TCW15 or TCW10. Instead of a 78mm outside diameter, the major diameter is 82mm. The TCW76 sports a 56mm inducer. This translates into a 47-trim relationship. This compressor is best suited for mid-to-high boost applications. The best efficiencies are in the 1.7 to 2.2bar (25-32psi) boost pressure range. As for horsepower potential, the TCW76 is best for applications in the 470 to 520 flywheel horsepower range.
The TCW77 compressor also shares an 82mm outside diameter compressor wheel like the TCW76. However, the inducer of the compressor is 61mm (a 5mm increase from the TCW76). This translates into a 55-trim relationship. This compressor is best suited for high boost applications. The best efficiencies are in the 2.1 to 2.6bar (30.5-38psi) boost pressure range. As for horsepower potential, the TCW77 is best for applications in the 550 to 600 flywheel horsepower range.