Flex
Taxes included. Shipping calculated at checkout.
Couldn't load pickup availability
Signature F55 Sound | Fast Spool | Built for Power
Take your 4JJ1 build to the next level with the FLEX PRO R31-R V2 Turbo Kit, also known as the Mini F55. This 44mm gated turbo delivers rapid lowβmid spool, sharp throttle response and the iconic F55 whistle / StuStuStu chatter β making it a perfect upgrade for daily driving, touring and performance applications.
Modifications may be required to fit this turbo
β οΈ INSTALLATION NOTES: Some installs may require trimming/drilling the manifold, a 44mm dump pipe, and EGR delete.
Complete kit with essentials for a clean installation.
Get the most from your Mini F55:
For off-road / competition use only. EGR removal and turbo modifications may affect compliance. Check local regulations before purchase.
Q: Is this a direct bolt-on for all 4JJ1 models?
A: Fitment suits common 4JJ1 applications but usually requires minor manifold work, a 44mm dump pipe and EGR delete.
Q: Do I need a tune after installing the Mini F55?
A: Yes β an ECU remap is recommended to set safe boost, rail pressure and fueling for best results.
Q: What boost should I run?
A: The turbo is capable of up to 35 PSI. Your tuner will set safe targets based on injectors, intercooler and usage.
Q: Will it pass a roadworthy with EGR deleted?
A: No β EGR removal may not be legal in your region. This kit is sold for off-road/competition use only where permitted.
Q: What else should I upgrade?
A: We recommend a quality intercooler, 3" exhaust, accurate boost/EGT monitoring, and ensuring oil feed/return are clean. Always prime the turbo with oil before first start.
Q: What makes the "StuStuStu" sound?
A: The iconic sound comes from the gated wastegate actuator combined with the turbo's compressor design. It's the signature F55 whistle and chatter that enthusiasts love.
Q: Is this suitable for daily driving?
A: Yes β when properly tuned, the Mini F55 offers a great balance of performance and drivability for street and touring use.
Q: What's included in the kit?
A: Complete kit includes the R31-R V2 turbo, gaskets, oil feed/return fittings, and Liqui Moly turbo pre-lube.
FLEX Mini F55 turbo kit. StuStuStu chatter. Fast spool. 35 PSI capable. Complete kit with pre-lube. Signature performance sound.
Disclaimer: Common Rail Cowboys is not affiliated with Holden, Isuzu Motors, or FLEX Thailand. Installation should be performed by a qualified technician. Proper tuning and supporting modifications are the buyer's responsibility.
