The Lexus IS250 is a reliable, good looking, and fuel efficient car, but in stock form it is not exactly a fast car! The good news is that the 4GR-FSE 2.5L engine is a robust and under-stressed engine that features forged crankshaft, forged connecting rods, piston oil cooling squirters, and a robust oiling system, not to mention an excellent direct injection fueling system. So after months of development and testing on our 150,000 mile 2008 IS250 shop car, we were able to DOUBLE the stock output of the engine to achieve performance rivaling and surpassing other popular tuner cars such as GTIs, WRXs, 370z’s, and others!
Depending on the desired power level, our kits are available with either a Stage I pulley (up to 13psi boost) or a Stage II pulley (up to 15psi boost). Both Stages can be upgraded with either e85 gauge kit for ethanol content monitoring, or an AEM water/meth injection system (see dyno results).
- Power: Stage I customer running on 93 octane fuel can expect to make about 320-330 wheel horsepower on a Dynojet dyno, STD correction) at approximately 11-13 psi peak boost pressure utilizing stock exhaust manifold and a basic performance exhaust system. For stage II power levels we recommend e85 blended fuel or water methanol injection to maintain reliability. Stage II customers can expect to make approximately 360-370 whp with stock exhaust manifolds and basic aftermarket exhaust system.
- Tuned ECU: Each SC kit received our OBD programmer, allowing you to load custom maps and updates to your factory ECE. We have logged countless development hours perfecting our ECU tune for the IS250 for ultimate reliability and drivability.
- Supplementary External Fuel computer and injector: User tunable fuel control can be adjusted in real time. In the future this computer even allows us the option to increase injector size, and add true flex fuel control for e85 applications, something that is currently under development.
- Rotrex Supercharger: c38-81 (largest Rotrex SC). Rotrex SC's are extremely efficient and quiet due to their planetary drive system which spins up to 90,000 rpm, much like a turbocharger. The c38-81 will support up to 400+whp, depending on future staged upgrades we offer. No need to every upgrade your SC to make more power!
- Dry Sump SC oiling system with Oil Cooler: Our system comes with an autonomous dry sump oiling system and oil cooler, so our system does not require plumbing oil lines to the engine, or adding any additional heat input to the engine’s cooling system.
- Dedicated Oiling System: Our system comes with an autonomous dry sump oiling system and oil cooler, so our system does not require plumbing oil lines to the engine, or adding any additional heat input to the engine’s cooling system.
- Dedicated Drive System: Rather than using the accessory belt to drive the SC, we designed a dedicated drive system that allows us to achieve the necessary belt tension for a reliable SC drive, without overstressing the alternator, water pump, and AC bearings.
- Automatic Belt Tensioner System: No need to constantly adjust or tighten the SC belt, our automatic tensioner will maintain proper tension for the life of the belt.
- Optional High Quality Turbosmart "Big Bubba" billet blow off Valve: Adequate venting is essential for SC responsiveness, reliability, and drivability, so rather than use a cheap plastic or miniature BOV, we went the extra mile and use a premium BOV.
- Custom Air/Air bar and plate Intercooler: We use a large intercooler core, and manufacture our intercoolers in-house. These intercoolers are extremely high quality, and are capable of supporting up to 500+whp, so there is no need to ever upgrade!
- Quality and Warranty: As all our other products, this kit enjoys our well known stringent quality standards for product development, manufacturing and service backed by 2-3 years Rotrex Warranty on SC, plus 1 year warranty on all other components supplied with your kit.
Check it out compared to Porsche 991 Carrera S!
Please watch this video of 3IS250 acceleration: