The various embodiments disclosed herein relate to systems and methods of improving fuel economy of internal combustion engines. In particular, the systems and methods relate to improving fuel economy of internal combustion engines by increasing the laminar flame speed (LFS) of fuel and hydrogen gas mixture. By increasing the laminar flame speed of the mixture, amount of carbon-based fuel that undergoes combustion increases. This may provide the advantage of minimizing overall fuel consumption by the engine, resulting in fuel savings. This may also provide the advantage of minimizing greenhouse gas emissions by the engine, resulting in environmental benefits.