Vectrace

From http://vectrex.wikia.com/wiki/Vaboom!/Vectrace

Also known as Ronen’s Game Cart, Vaboom!/Vectrace is a bit of an unusual homebrew entry, due to it containing one of the very few racing games for the Vectrex (Vectrace). And it might also seem to be a bit unusual for another Kaboom! clone to be made for the system as well (Vaboom!, as the first clone, Spike’s Water Balloons, from the All Good Things cartridge, was released four years earlier). Arguably, this odd pairing of games makes this cartridge still stand out a bit.

Source: TheGamesDB