SUTuner Live

Find, tune, and compare SU carburetor needles — on your phone, not in a 20-year-old spreadsheet. SUTuner replaces the old SU needle spreadsheet with a modern needle-matching tool covering all three SU jet families — 0.090", 0.100", and 0.125" — and 683 real needles. Enter the diameters you want at any station and it ranks the closest-matching needles, or start from a reference needle and tell it to search a specific region richer or leaner — it finds the needle that gets you there with the smallest change everywhere else. Every needle's profile is charted two ways — raw diameter and actual flow area — and you can overlay up to four needles at once, normalized at idle so the shapes are directly comparable. A built-in reference of 89 factory vehicle applications (Jaguar, MG, Austin-Healey, Mini, Triumph) links straight to real needle data, and if you're tuning on a dyno, SUTuner can import your logged AFR and plot it against the needle's own station chart so you can see exactly which region is running rich or lean. FEATURES • Search by desired diameter at any of 16 stations, sorted by total deviation or least-squares fit • Tune a specific region — Idle, Low Cruise, Mid Cruise/Low Accel, Hi Cruise, Hi Accel, or the whole needle — richer or leaner from a reference needle, ranked by smallest disruption elsewhere • Compare up to 4 needles at once: diameter and flow-area charts, normalized-at-idle or raw • All three SU jet sizes — 0.090", 0.100", and 0.125" — 683 needles total • 89 factory vehicle applications across five marques, with standard/rich/lean needle codes and spring-type data • Import a dyno AFR log (CSV) and see it plotted against station, with editable target AFR bands per zone • Works fully offline — no accounts, no ads, no tracking, no network access at all