Bushy became part of the group's classic lineup, along with vocalist and keyboardist Doug Ingle, guitarist Erik Brann, and bassist Lee Dorman.

They are best known for the 1968 hit "In-A-Gadda-Da-Vida", providing a dramatic sound that led the way towards the development of hard rock and heavy metal music.

He rejoined the group when the band reformed in 1974, playing on its fifth and sixth albums, Scorching Beauty and Sun and Steel, both released in 1975.

Their music has found a significant impact on the international rock scenes, influencing numerous acts such as Black Sabbath, AC/DC, Rush, Alice Cooper, Mountain, Uriah Heep, Soundgarden, Stone Temple Pilots, Slayer, King Gizzard & the Lizard Wizard, and Queens of the Stone Age.

On August 29, 2021, Iron Butterfly issued a statement that Bushy had died that morning at the UCLA Medical Center in Santa Monica following a battle with esophageal cancer, at the age of 79.