Ford 351C Cleveland Dual Idler Noisy Timing Gear Drive Set you must use one that

you must use one that is also approved as street legal for your application

Chevy Caprice

They also offer the potential for improved fuel economy by making the engine more efficient

Designed for C4 transmissions in competitive environments where RPM levels approach or exceed 8

fuel rail set

Ford 351C Cleveland Dual Idler Noisy Timing Gear Drive Set you must use one thatSpeedmaster gear drives are great for you folks who want better timing. Their dual idler design has CNC machined components and they are easy to install. These drives fit under your stock timing cover and come complete with instructions. Minor machining may be required on some applications.