K24 RWD gearing & drivability checker

Pick an adapter-ready RWD transmission, enter your car's weight, rear axle ratio and tire size, and get an estimated drivability score. Add a turbo to see power, spool and how boost changes the picture.

Estimates for entertainment and general information only. Verify everything with a qualified mechanic before buying parts or building. Full disclaimer

Feasibility and notes

    RPM vs speed by gear

    Estimated engine output

    Horsepower Torque (lb-ft) Dashed: naturally aspirated

    Gear breakdown

    All five transmissions with your car

    Same weight, tire, engine and turbo settings. "Best axle" is the common ratio that scores highest for that gearbox.

    Turbo size vs estimated power

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    How the estimate works

    Drivability is a weighted blend of six gearing factors: highway cruise RPM (25%), launch and first gear (20%), gear spacing (20%), around-town gearing (15%), power-to-weight (10%), and response and traction (10%). Turbo builds shift the targets: cruise can sit lower, and gear spacing is judged against staying above spool.

    Turbo power uses rule-of-thumb math: naturally aspirated output scaled by boost pressure at about 85% efficiency, capped by a compressor flow limit of roughly 0.18 × inducer² (mm) crank horsepower. Spool is estimated from inducer size on a 2.4L. Real results depend on the exact turbine, A/R, manifold, fuel, tune and intercooling.

    Transmission torque ratings are rough community figures, not manufacturer guarantees; clutch, driveshaft and differential limits aren't modeled. Gear ratios should be confirmed against your specific transmission code before buying parts. This is a planning tool, not an engineering analysis.

    Disclaimer

    For entertainment and general information only. The scores, horsepower figures, torque limits, spool estimates and other results on this page come from simplified rule-of-thumb models and publicly available information. They are not engineering calculations, professional advice or a guarantee of how any vehicle, engine or part will perform.

    Use at your own risk. Engine swaps, turbocharging and drivetrain modifications can cause mechanical failure, property damage, serious injury or death. Always have your plans and work reviewed by a qualified mechanic or engineer, follow manufacturer specifications, and verify gear ratios, part numbers and fitment for your specific vehicle.

    No warranty; limitation of liability. This tool is provided "as is," without warranties of any kind, express or implied, including accuracy, completeness or fitness for a particular purpose. To the fullest extent permitted by law, the owner and operators of this site are not liable for any loss, damage, cost, injury or claim arising from your use of this tool or reliance on its results, including parts purchased, labor, repairs, vehicle damage or downtime.

    Know your local laws. Engine swaps and modifications may affect emissions compliance, vehicle registration, inspections, insurance coverage and manufacturer warranties. You are responsible for making sure your build is legal where you live and drive. Some parts may be sold for off-road or competition use only.

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