Toyota 1GR TRD Supercharger Pulley Upgrade, +20WHP, +25WTQ!

The Toyota X-Runner community is a cool bunch. These guys and girls love their trucks, and they love to modify them. One of the more popular big power adders is the TRD Supercharger. Rated at 6psi the TRD SC adds a very noticeable kick to the truck’s rear-end and makes the 1GR engine much more responsive. We wanted to see if we could improve on an already great modification, while keeping the 1GR streetable and dependable.

TRD Supercharger for the Toyota 1GR (XRunner, FJ Cruiser, Prado)

THE TRUCK & PARTS
Enter Mickey Le and his 2005 Speedway Blue X-Runner. Mickey is local to our Houston showroom and was kind enough to bring his SWB to our garage for some testing. His truck was only modified with an NST CR-Lite Kit, TRD Intake, and Magnaflow Exhaust, making it perfect for establishing a solid baseline. (Mickey’s truck has changed a bit since then and we’ll have more info on it in an upcoming entry, so stay tuned!) After a few test-fitting sessions, it was time to hit the dyno. We made the short trip to our favorite tuning shop in Houston, Carboy, and ran a few baselines. While there, the finalized version of the NST Overdrive SC Kit was installed (in less than one hour) with ease. The engine and ECU remain completely stock otherwise, as no other modifications are necessary for the extra boost levels. Not even a different belt is necessary. We were ready to hit the dyno again to analyze psi and air-fuel readings. By using Carboy’s Dynojet for pre and post evaluations on the same day, we were able to keep certain variable weather conditions in check, such as temperature, humidity, or percipitation.

NST Overdrive Kit; crank ring, water pump, idler, tensioner

THE RESULTS
Most X-Runners should post just over 300HP at the stock boost level of 6psi with the TRD SC. Mickey’s Truck posted some very impressive numbers on the dyno, with Max Power recorded at 341.73 and Max Torque coming in at 351.37. Doing the complicated math tells us that the NST Overdrive Kit has netted us an extra 20 WHP and 25 WTQ, while remaining in the efficiency range of the stock engine management and fuel system.

Obviously higher numbers are possible with extra tuning and certain supporting modifications require custom tuning, but our testing was meant to determine whether or not the TRD ECU Reflash is capable of handling an extra 1.5psi on a relatively stock truck. The obvious answer is YES!

341 WHP, 351 WTQ… Not too shabby!