The 2nd Generation D100 debuted midway through 1965, now sporting two headlights instead of four. Three new engines were added as options including a 440 cubic inch big block during the 2nd Generation's production run. In 1968, a the D100 received a midlife facelift and new trim levels including the Adventurer and "The Dude" trims.

Hays Twister Full Race Torque Converters feature an anti-balloon plate for use with nitrous, superchargers, and turbos. They are designed to accommodate any mixture of modifications including higher compression ratios, aftermarket camshafts, aftermarket cylinder heads, lower gear ratios, and vehicle weight loss.