SUTuner
SU Needle Finder & Tuner
About
This app helps you find and tune SU carburetors by replacing traditional spreadsheets with a digital tool. It allows you to match needles based on desired diameters, adjust specific regions for richer or leaner performance, and compare needle profiles visually. It also includes a reference for factory applications and the ability to import dyno logs.
What's New in SUTuner
1.0
August 20, 2026
Developer apps
FAQ
What is SUTuner used for?
SUTuner is a digital tool designed to replace traditional SU needle spreadsheets. It helps users find the closest matching needles based on desired diameters, tune specific regions of the needle for richer or leaner performance, and compare different needle profiles.
How does SUTuner help with tuning?
You can select a region of a needle (like Idle or Hi Cruise) and instruct SUTuner to find real needles that make that specific region richer or leaner. It ranks these by the smallest change in other regions, ensuring precise adjustments.
Can I compare different carburetor needles with SUTuner?
Yes, SUTuner allows you to overlay up to four needles at once on diameter and flow-area charts. This visual comparison, normalized at idle, makes it easy to see how different needle shapes compare directly.
Does SUTuner work offline?
Yes, SUTuner is designed to work fully offline. It does not require any network access, accounts, or tracking, ensuring all your data remains on your device.
What vehicles are covered by SUTuner's application reference?
SUTuner includes a built-in reference for 89 factory vehicle applications. These span brands like Jaguar, MG, Austin-Healey, Mini, and Triumph, detailing standard, rich, and lean needle codes, and spring types.
Can I import dyno data into SUTuner?
Yes, SUTuner supports importing logged AFR data from a dyno (in CSV format with vacuum, MAP, or PSI). It plots this data against the needle's station chart with editable target bands to identify rich or lean regions.
What is the price of SUTuner?
SUTuner is a paid application priced at $9.99. This one-time purchase grants you access to all its features without any subscriptions or in-app purchases.
Is SUTuner suitable for beginners?
While SUTuner offers advanced tuning capabilities, its user-friendly interface and visual comparison tools can assist both experienced mechanics and dedicated enthusiasts in understanding and optimizing their SU carburetors.
