I found some interesting stuff on geared Lycomings:
6cyl; GO-435; 210hp@3000rpm-260@3400; 1941-1977; Wt = 407-458#; TC = 228 on 8/30/44.
Geared to 0.642 (77:120).
6cyl; GO-480; 260hp@3000rpm-285@3100; 1954-1978; Wt = 432-464#; TC = 275 on 4/21/54.
Also built by BMW in Germany (TC = 7E1, dated 10/18/60) and by Piaggio in Italy.
All versions geared to 0.642 (77:120), except the GO-480-C3A6 and GO-480-E1A6 to 0.640 (16:25).
6cyl; GSO-480; 320hp@3200rpm; 1955-1969; Wt = 498-517#; TC = 284 on 6/30/55.
Geared to 0.642 (77:120); Military O-480-1.
6cyl; IGSO-540; 360hp@3200rpm; 1960-1978; Wt = 522-541#; TC = 1E7 on 6/17/60.
Geared to 0.642 (77:120).
6cyl; IGO-540; 325hp@3000rpm; 1960-1977; Wt = 500-517#; TC = 1E11 on 10/28/60.
Geared to 0.642 (77:120).
6cyl; TIGO-541; 400-450hp@3200rpm; 1968-present; Wt = 663-714#; TC = 19EA on 11/19/68.
Geared to 0.667 (2:3).
Jim
6cyl; GO-435; 210hp@3000rpm-260@3400; 1941-1977; Wt = 407-458#; TC = 228 on 8/30/44.
Geared to 0.642 (77:120).
6cyl; GO-480; 260hp@3000rpm-285@3100; 1954-1978; Wt = 432-464#; TC = 275 on 4/21/54.
Also built by BMW in Germany (TC = 7E1, dated 10/18/60) and by Piaggio in Italy.
All versions geared to 0.642 (77:120), except the GO-480-C3A6 and GO-480-E1A6 to 0.640 (16:25).
6cyl; GSO-480; 320hp@3200rpm; 1955-1969; Wt = 498-517#; TC = 284 on 6/30/55.
Geared to 0.642 (77:120); Military O-480-1.
6cyl; IGSO-540; 360hp@3200rpm; 1960-1978; Wt = 522-541#; TC = 1E7 on 6/17/60.
Geared to 0.642 (77:120).
6cyl; IGO-540; 325hp@3000rpm; 1960-1977; Wt = 500-517#; TC = 1E11 on 10/28/60.
Geared to 0.642 (77:120).
6cyl; TIGO-541; 400-450hp@3200rpm; 1968-present; Wt = 663-714#; TC = 19EA on 11/19/68.
Geared to 0.667 (2:3).
Jim